• 전기학회논문지
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• 제67권3호
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• pp.460-466
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• 2018

For the efficient energy consumption in an urban railway station, it is necessary to know the patterns of electrical loads for each usage in detail. The electrical loads in an urban railway station have different characteristics from other normal electrical load, such as the peak load timing during a day. The lighting, HVAC, communication, and commercial loads make up large amount of electrical load for equipment in an urban railway station, and each of them has the unique specificity. These loads for each usage were estimated without measuring device by the polynomial regression method with big data such as total amount of electrical load and weather data. In the simulation with real data, the optimal polynomial regression model was third order polynomial regression model with 9 or 10 independent variables.

• 전기학회논문지
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• 제67권11호
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• pp.1542-1548
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• 2018

When any faults occurred in electrical railway system, operators need to analysis it quickly and accurately. Existing COMTRADE based analysis tools are not enough to analysis faults occurred in electrical railway system. In this paper, it presents some functions to fault analysis for electrical railway system based on fault data formatted COMTRADE. These functions are implemented in PSCAD/EMTDC and it can be shown that analyzed results against actual electrical fault cases which were occurred in the electrical railway power system.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 춘계학술대회
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• pp.373-375
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• 2016

전 세계적으로 스마트 환경의 발전에 따라 데이터의 폭발적인 증가로 인해 빅 데이터의 분석이 각광을 받고 있다. 금융, 유통, 제조, 재난 등 빅 데이터의 활용 분야에서 분석 및 활용에 대한 결과 활용이 중요하게 언급되고 있다. 본 연구에서는 전자상거래 시스템에서 빅 데이터의 성숙도 조사 결과를 기반으로 Business Process에 미치는 영향을 분석하여 데이터 분석 및 이의 활용에 미치는 영향 요소를 제시하고자 한다.

• Journal of Electrical Engineering and Technology
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• 제2권2호
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• pp.172-177
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• 2007

Wavelet transforms provide basis functions for time-frequency analysis and have properties that are particularly useful for the compression of analogue point on wave transient and disturbance power system signals. This paper evaluates the compression properties of the discrete wavelet transform using actual power system data. The results presented in the paper indicate that reduction ratios up to 10:1 with acceptable distortion are achievable. The paper discusses the application of the reduction method for expedient fault analysis and protection assessment.

• 한국멀티미디어학회논문지
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• 제13권12호
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• pp.1814-1819
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• 2010

Since 1987, when statistical analyzing guide for thermal life test of Accelerated Life Test(ALT) was proposed as ANSI/IEEE Std 101, this guide has been used widely for many experiment data. Shim(2004) had done Monte Carlo simulation to compare life of two different systems or materials, based on statistic values obtained from ANSI/IEEE Std 101 data. In this study, a profile analysis is proposed for comparing life of two different systems or materials, and some examples using pre-existing data are given.

• Journal of Electrical Engineering and Technology
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• 제1권2호
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• pp.145-152
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• 2006

This paper presents a windows application for voltage sag analysis and effective data visualization. The developed Voltage Sag Analysis Tool (VSAT) was designed by using the Object-Oriented Programming (OOP) concept and C++ programming language. The VSAT provides basic functions for voltage sag analysis such as power flow analysis, short circuit analysis and stochastic analysis. In particular, the VSAT provides effective data visualization through computer graphics and animation. Analysis results are expressed realistically and intuitively on geographical display. The Graphic User Interface (GUI) of VSAT was designed specifically for voltage sag analysis. In this paper, the development and implementation of VSAT is presented. In order to demonstrate the capabilities of VSAT, it is used to analyze the Jeju Island power system in South Korea.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.327-330
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• 2004

Because of its effectiveness for the PD(partial discharge) pattern recognition, PSA(Pulse Sequence Analysis) has been considered as a new analytic method instead of conventional PRPDA(Phase Resolved Partial Discharge Analysis). However, PSA has a big problem that can misanalyze patterns in case of data missing resulting from poor sensitivity because it analyses the correlation between sequential pulses, which leads to hesitate to apply it to on-site. Therefore, in this paper, the problems of PSA such as data missing and noise adding cases were investigated. For the purpose, PD data obtained from various defects including noise adding data were used and analysed, The result showed that both cases can cause fatal errors in recognizing PD patterns. In case of the data missing, the error depends on the kinds of defect and the degree of degradation. Also, it could be noticed that the error due to adding noises was larger than that due to some data missing.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제6권8호
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• pp.353-358
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• 2017

전신주와 같은 전력 설비에는 스마트한 서비스를 위한 다양한 종류의 센서가 포함되어 있으며, 온도 정보는 전력 설비의 정상 동작 상태를 판단하는 중요한 요소 중 하나이다. 본 연구에서는 칼만 필터(Kalman Filter)와 앙상블 모델(Ensemble Model)을 이용해 스마트 전력 장치의 상태를 판단할 수 있도록 장치의 온도 분석 방법을 제안했다. 제안 된 접근 방식은 서로 다른 위치에 설치된 센서로 부터 수집된 정보 중 온도 데이터를 분류하고 칼만필터 및 앙상블 모델을 사용하여 온도 변화의 특성을 분석했다. 세부적으로 수집된 온도 데이터로부터 기상 온도 데이터와 같은 외부 인자를 제거하고 전력 장치의 각 위치로부터의 실제 장치의 온도값만을 분석했으며, 이 과정에서 칼만필터를 사용하여 오류 데이터를 제거하고 앙상블 모델을 사용하여 매 시간 정상 동작하는 전력 설비의 온도 평균값을 산출했다. 온도 분석에 대한 결과와 논의는 전력 데이터에 분석 결과에 명확하게 설명되어 있다. 마지막으로, 분석된 데이터를 통해 전력 장치가 정확히 동작하는 지를 판단할 수 있는 온도값의 정상범위를 확인하였다.

• 조명전기설비학회논문지
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• 제18권1호
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• pp.60-66
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• 2004

전기부하설비의 전압, 전류, 전력, 고조파 등의 분석을 위해서는 수학적 모델링 보다는 실제 계측을 통한 전력분석이 필요하고 이를 통해 전기설비의 효율적인 관리, 에너지 절약 및 사고 예방에 필요한 대책을 수립할 수 있다. 특히 비선형 부하에 의해 발생되는 고조파의 대책수립을 위해 계측을 통한 전력분석이 필수적이다. 따라서 본 논문에서는 전기부하설비에 공급되는 전력을 측정하고 분석할 수 있는 저가형 데이터 획득 시스템을 DSP 기반으로 개발하였고 이를 실제 전력계통에 설치하여 전력 및 고조파의 측정과 분석을 수행함으로써 그 성능을 입증하였다.

• Journal of Electrical Engineering and Technology
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• 제8권4호
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• pp.840-849
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• 2013

This paper presents a statistical approach to analyze electrical tree inception voltage, electrical tree breakdown voltage and tree breakdown time of unsaturated polyester resin subjected to AC voltage. The aim of this work was to show that Weibull and lognormal distribution may not be the most suitable distributions for analysis of electrical treeing data. In this paper, an investigation of statistical distributions of electrical tree inception voltage, electrical tree breakdown voltage and breakdown time data was performed on 108 leaf-like specimen samples. Revelations from the test results showed that Johnson SB distribution is the best fit for electrical tree inception voltage and tree breakdown time data while electrical tree breakdown voltage data is best suited with Wakeby distribution. The fitting step was performed by means of Anderson-Darling (AD) Goodness-of-fit test (GOF). Based on the fitting results of tree inception voltage, tree breakdown time and tree breakdown voltage data, Johnson SB and Wakeby exhibit the lowest error value respectively compared to Weibull and lognormal.