• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.68-70
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• 2001

Because of the difficulty of acquiring new generation sites and right- of-way, additional units have been added to the existing generation sites and the transmission system has been developed into highly meshed configuration. The reliable operation of power systems has been restricted by this system characteristics. The enhancement of system analysis techniques and establishment of appropriate measures have been required in this situation. In addition the deregulation of electric power industry in Korea would give rise to better tools fur power system analysis and control. In this paper, dynamic models were developed and stability studies were implemented using developed dynamic models of EUROSTAG and compared with the simulation results of PSS/E.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.9-11
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• 2003

In power system planing and operation, voltage and reactive power control are very important. The voltage deviation and system losses can be reduced through control of reactive power sources. In general, there are several different reactive power sources, we used UPFC and switched shunt capacitor to improve the voltage profile and to reduce system losses in this study. Since there are many switched shunt capacitors in power system, so it is necessary to coordinate these switched shunt capacitors. In this study, Genetic Algorithm(GA) is used to find optimal coordination of UPFC and switched shunt capacitors in a local area of power system. In case study, the effectiveness of the proposed method is demonstrated in KEPCO's power system. The simulation is performed by PSS/E.

• 전기학회논문지
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• 제64권5호
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• pp.661-666
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• 2015

This paper proposes a method for solving running cost problem by minimizing switching reactive power compensation devices. An objective function was modeled by calculating the weighting value of cost, and a solution was derived using ILP. This paper suggests optimal coordinative control method between FACTS, Shunt Reactors, Capacitors and OLTC. Therefore, it is valuable for decision maker in determining order and capacity of devices which gaining a voltage stabilization. As a result, the objectives of voltage stabilization and cost minimization were achieved simultaneously. This realizes the economic efficiency of the system. We start by showing how to solve systems of linear equations using the language of pivots and tableaus. The effectiveness of this technique is demonstrated in modified PSS/E MIGUM 45 bus system. The simulation results show the effectiveness of this algorithm by comparing the outcome withseveral established methods.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.416-417
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• 2007

통신 및 IT 기술의 발달로 실시간 기반 전력계통 해석 기능은 점진적으로 발전하고 있으며, 우리나라도 2003년부터 상태추정, 상정고장 등 실시간 해석기반 계통해석을 수행하고 있다. Network Analysis(NA) 기능으로 언급되는 EMS 계통해석 기능은 실시간 전력계통의 안전도를 평가, 취약개소를 도출함으로써 비상시 신속하고 안정적인 계통운영에 활용되고 있다. 본 논문에서는 EMS NA 기능 중 실시간 무효전력 최적화 제어기능인 VVD(Voltage VAR Dispatch) 기능을 소개하고 이의 활용방안을 제시하고자 한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.427-428
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• 2007

'07년 하절기 최대부하시 전력계통을 대상으로 고장계산, 조류분석 및 안정도 해석을 통한 계통운영상의 문제점을 분석하고 이에 대한 대책을 수립 시행함으로써 계통의 안정운영을 도모하고, 대학이나 연구소 등의 계통해석 업무에 도움을 주고자 한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전력기술부문
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• pp.158-161
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• 2004

This paper presents practical applications of reactive power and voltage planning to obtain voltage stability and operational voltage level for 2005 year summer peak Korea power system. It also describes the new electric facilities, operation criteria, voltage levels, MVAr flows, reactive power reserves in each control area. And reactive compensation devices are installed to maintain established voltage levels and stability margins. This simulation results show the improvement of voltage levels and the increase of reactive margins & interface flow margins. Finally, the paper reports the necessity of dynamic reactive reserves. It can be applied to analysis reactive compensation requirements and P-V & V-Q curves by PSS/E & VSAT.

• 한국재난정보학회 논문집
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• 제3권2호
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• pp.95-117
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• 2007

With rapid changes taking place in every field, the expansion and specialization of various social service activities are one of the characteristics of the modem society. However, the increase of crimes and inefficiency of public police service to cope with this situation have caused discontent and distrust on the service among the public, making people more inclined to solve safety-related problems by themselves. Private Security Service(PSS) and Private Investigation Service(PIS) were introduced to satisfy these needs. In the area of PIS, Public Investigation Service System(PISS) has been established for a quite long time in foreign countries. However in Korea, PIS is being provided by unregulated service providers such as errand service center due to the lack of legal system, causing many problems related with illegal practices by the service providers. This paper is the result of the research on how to adopt a relevant PISS in Korea and develop it in the future. This kind of research is much needed to curb the rising illegal practices of the errand service centers, complement the insufficient operation of public police service, and strengthen the competitiveness of our country by taking more efficient actions in the changing public security environment. Based on the research, this paper also examines positively the possibility of introduction of PIS in Korea. This paper also recommends a prompt enactment of PIS regulation and improvement on the legal environment for such introduction of the relevant and suitable PISS in Korea.

• Journal of Electrical Engineering and Technology
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• 제7권5호
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• pp.689-697
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• 2012

This paper proposes a new coordinated voltage control scheme between STATCOM (Static Synchronous Compensator) and reactive power compensation devices, such as shunt elements(shunt capacitor and shunt reactor) and ULTC(Under-Load Tap Changer) transformer in a local substation. If STATCOM and reactive power compensators are cooperatively used with well designed control algorithm, the target of the voltage control can be achieved in a suddenly changed power system. Also, keeping reactive power reserve in a STATCOM during steady-state operation is always needed to provide reactive power requirements during emergencies. This paper describes the coordinative voltage control method to keep or control the voltage of power system in an allowable range of steady-state and securing method of momentary reactive power reserve using PSS/E with Python. In the proposed method of this paper, the voltage reference of STATCOM is adjusted to keep the voltage of the most sensitive bus to the change of loads and other reactive power compensators also are settled to supply the reactive power shortage in out range of STATCOM to cope with the change of loads. As the result of simulation, it is possible to keep the load bus voltage in limited range and secure the momentary reactive power reserve in spite of broad load range condition.

• Journal of Electrical Engineering and Technology
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• 제6권4호
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• pp.484-492
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• 2011

Power system analyses, which involve the handling of massive data volumes, necessitate the use of effective visualization methods to facilitate analysis and assist the user in obtaining a clear understanding of the present state of the system. This paper introduces an interface that compensates for the limitations of the visualization modules of dynamic security assessment tools, such as PSS/e and TSAT, for power system variables including generator rotor angle and frequency. The compensation is made possible through the automatic provision of dynamic simulation data in visualized and tabular form for better data intuition, thereby considerably reducing the redundant manual operation and time required for data analysis. The interface also determines whether the generators are stable through a generator instability algorithm that scans simulation data and checks for an increase in swing or divergence. The proposed visualization methods are applied to the dynamic simulation results for contingencies in the Korean Electric Power Corporation system, and have been tested by power system researchers to verify the effectiveness of the data visualization interface.

• 전기학회논문지
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• 제66권11호
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• pp.1554-1560
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• 2017

Prepare a lose of 765kV transmission route in power system operation condition, there are some Special Protection Scheme(SPS)s in Korean power system. These SPS can make some preselected generators are tripped to avoid generator overspeed. Because of many of the new large power plants are installed to existing power generation sites due to the siting problem, the number of generator tripped by SPS should be increased. But that can be a cause of system frequency change under the Under Frequency Relay(UFR) 1st pickup level 59.0Hz. Therefore generation constraint should be considered until new transmission lines are installed. In this paper, we propose the ESS application for generation constraint mitigation by frequency damping control of ESS. To analysis an effect of ESS application, we use PSS/E dynamic simulation tool, CBEST model and controller model. The proposed ESS application is applied to the empirical Korean power system.