• 한국통신학회논문지
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• 제35권8B호
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• pp.1251-1258
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• 2010

단방향 전력망에 정보통신 기술을 접목하여 전력공급자와 소비자가 양방향 실시간 정보를 교환함으로서 에너지 효율을 최적화하는 스마트 그리드의 핵심인 지능형 원격검침 시스템에 대한 연구개발 및 사업화가 전 세계 전력 회사별로 활발히 진행 중에 있다. 본 논문에서는 KEPCO가 대규모 사업화를 추진 중에 있는 지능형 원격검침 시스템의 구성도, 설계된 핵심 단말 및 주요 기능, 관련 통신 기술 및 부가 서비스를 소개하고 기술적 특성과 사업 방향성을 제시하고자 한다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권4호
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• pp.208-216
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• 2005

Recently, the study of islanding phenomenon, maintains its operation even when the utility grid is removed has lead to the trend of utility interactive inverters in photovoltaic generation systems. In this paper, a novel Anti-islanding method is presented. the proposed method can keep the real average power component constant by MPPT control and cause the load current frequency with only change of reactive power component under the islanding condition. its periodical change of Reactive power component can decrease the NDZ(Non-Detective zone) so that the detection of various loads will be possible. the insufficient effect if additional reactive power component to the grid is proved theoretically and the islanding detection is also confirmed from a experimental result with a inverter for 3kW photovoltaic generation system applied the proposed Anti-islanding method.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.229-232
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• 2008

The Central East Sea Tsunami caused huge damage to the eastern coast of the Korean Peninsula, eapecially Imwon port was damaged relatively strongly beacause of water depth variation which makes the wave concentration on this port. there are many virtual tsunami in east sea which has a possibility of happening. So, it is very important to expect the region which may be damaged by vritual tsunmis. In this study, modified dispersion-correction terms are used. The modified scheme has the advantage of using the constant spatial grid size and time step size even in real topography. Dynamic linking technique and staggered grid system are used. Using this model some cases of virtual tsunami was simulated and check the region which is occured maximum wave heights on the eastern sea of the Korean peninsula.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.179-182
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• 2008

This study simulated the flood inundations of the Nakdong River catchment running through Yangsan, a small city located in the south eastern area of Korea by using the depth averaged two-dimensional hydrodynamic numerical model. The numerical model employs the staggered grid system including moving boundary and a finite different method to solve the Saint-Venant equations. A second order upwind scheme is used to discretize the nonlinear convection terms of the momentum equations, whereas linear terms are discretized by a first order leap-frog scheme(Cho and Yoon, 1998). The numerical model was applied to a real topography to simulate the flood inundation of the Yangsan basin. The numerical results for urban district are visualized in three dimension. These results can be essentially utilized to construct the three dimensional inundation map after building the GIS-based database in local public organizations in order to protect the life and property safely.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2014년도 전력전자학술대회 논문집
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• pp.538-539
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• 2014

The development of smart grid technologies will enable enhanced utilization of electric vehicles(EV) as portable energy storage devices which can provide power system-wide. Because significant increase of EV in the near future, V2G(Vehicle-to-Grid) system will soon become a reality. This paper presents the optimal method of a battery lifetime depending on depth of discharge(DOD) considering load leveling.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2006년도 가을 학술발표논문집 Vol.33 No.2 (A)
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• pp.181-184
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• 2006

최근 온라인 원격실험이 하나의 이슈로 되면서 지역적으로 분산된 실험 장비, 데이터베이스, 작업현장 등을 접근 하는 다양한 방식이 제안되고 있다. 다양한 모니터링 시스템이 존재하고 또한 개발 되고 있는 현황에서 본 논문은 분산 시스템 환경과 실시간 시스템을 어떻게 접목을 시키고, 여기에 Grid환경에서 제공하는 인증체계를 도입하는 모델을 구상하고 있으며, 실질적인 사용가치를 갖는 멀티 타겟 실시간 원격 모니터링 시스템을 제안한다. 실시간 시스템은 보다 정밀한 시간을 제공함으로서 실시간 적인 모니터링과 차후 저장된 데이터에 의한 세밀한 리뷰가 가능하게 한다. 본 시스템은 실시간 미들웨어(TMO)에서 제공하는 시간적 정확성 및 실시간과 Grid인증의 접목에 착안점을 두고 있으며 환경분야 실험모니터링 시스템이라는 현실적 모델의 구현을 통하여 본 시스템을 검증한다.

• 한국태양에너지학회 논문집
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• 제28권5호
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• pp.72-77
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• 2008

The purpose of this paper is to explain the real characteristics of generation system of large scale power system of high voltage the grid connected PV power system for electricity industry. Main system is made up PCS in the class 150kVA. and we studied commercial operation in Korea-Western Power Company,(Tae-An headquarter) with the capacity of module is 122.5 $kW_p$. On the average, power plant utilities' utilization is 12.71 percent and consumption rate is 6.66 percent. We operated normally since 25th, August 2005 without any other problems.

• International journal of advanced smart convergence
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• 제8권2호
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• pp.218-226
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• 2019

The use of Information and Communication Technologies (ICT) is the key to operate a change from the traditional manual reading of water meters and sensors to an automated system where high frequency data is remotely collected and analyzed in real time, one of the main components of a Smart Water Grid. The recent boom of ICT offers a wide range of both wired and wireless technologies to achieve this objective. We review and present in this article the most widely recognized technologies and protocols along with their respective advantages, drawbacks and applicability range which can be Home Area Network (HAN), Building Area Network (BAN) or Local/Neighborhood Area Network (LAN/NAN). We also present our findings and we give recommendations on the application of ICT in Smart Water Grids and future work needed.

• Journal of Power Electronics
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• 제19권5호
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• pp.1315-1325
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• 2019

Aiming at the negative sequence and harmonic problems in the operation of railway static power conditioners, an optimization compensation strategy for negative sequence and harmonics is studied in this paper. First, the hybrid RPC topology and compensation principle are analyzed to obtain different compensation zone states and current capacities. Second, in order to optimize the RPC capacity configuration, the minimum RPC compensation capacity is calculated according to constraint conditions, and the optimal compensation coefficient and compensation angle are obtained. In addition, the voltage unbalance ${\varepsilon}_U$ and power factor requirements are satisfied. A PSO (Particle Swarm Optimization) algorithm is used to calculate the three indexes for minimum compensating energy. The proposed method can precisely calculate the optimal compensation capacity in real time. Finally, MATLAB simulations and an experimental platform verify the effectiveness and economics of the proposed algorithm.

• Communications for Statistical Applications and Methods
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• 제29권4호
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• pp.403-411
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• 2022

This article presents an independence test between pairs of interval censored failure times. The Mantel-Haenszel test is commonly applied to test the independence between two categorical variables accompanied with a strata variable. Hsu and Prentice (1996) applied a Mantel-Haenszel test to the sequence of 2 × 2 tables formed at the grids which are composed of failure times. In this article, due to unknown failure times, the suitable grid points should be determined and the status of failure and at risk are estimated at those grid points. We also consider a weighted test statistic to bring a more powerful test. Simulation studies are performed to evaluate the power of test statistics under finite samples. The method is applied to analyze two real data sets, mastitis data from milk cows and an age-related eye disease study.