• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1906-1908
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• 2000

The central monitoring system with on-line diagnosis of high-voltage generator/motor stator insulation is developed. The system is capable of remote diagnosis and monitoring partial discharges of high-voltage generator/motor stator insulation. GOMS(Generator On-line Monitoring System) with maximum of 9 input channels can measure and analyze the status of high-voltage motor stator insulation by on-line. The measured and analysis data are brought to the central monitoring system via modem to build database. The central monitoring system can diagnose and monitor the insulation status of several high-voltage generator/motor at any time. The insulation status of those machines can be enhanced by the database on partial discharges.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.2052-2053
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• 2008

High voltage motors are the core equipment of electric generation facilities and need to guarantee stable operation. Therefore, keeping healthy state is of importance by means of insulation diagnosis periodically. However, if the diagnosis went through in the different circumstances such as temperature, humidity, and impedance applied to the test equipment, the trend analysis have no significance. This paper presents the experimental results supporting the importance of keeping the same conditions under insulation diagnosis.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2000년도 학술대회논문집
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• pp.89-93
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• 2000

Recently many research activities on the diagnosis of stator winding insulation of large rotating machines have been reported. Capacitive couplers are widely used as sensors for on-line partial discharge (PD) measurement of high voltage rotating machines. This paper presents laboratory test to compare Stator Slot Coupler (SSC), Resistance Temperature Detector (RTD), 80 [pF] coupler and 500 [pF] coupler for on-line PD measurement of rotating machines. And a novel on-line monitoring system for an insulation diagnosis is proposed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 일렉트렛트 및 응용기술
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• pp.148-151
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• 2002

In order to prevent the failures of underground distribution power cables we need to measure insulation condition in the field. Until now we used DC high voltage as a power source for the cable diagnosis but it was not proper method to the XLPE insulation cables because DC high voltage can affect sound insulation and can't diagnose exactly insulation degradation. For these reasons we imported isothermal relaxation current measurement system called by KDA-1 from germany but it's reliability did not proved in our URD cables. DC voltage decay measurement system was developed by domestic company but they don't have field experience. In this paper we tried to prove reliability of these two systems in the field. Through the field diagnosis and Ac breakdown test the two systems showed similar results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 E
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• pp.1692-1695
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• 1997

This paper describes the relationship between the various non-destructive parameters and the breakdown voltage for the 17 kV, 300 MVA and the 22 kV, 500 MVA generators stator bars with polyester and epoxy/mica insulation respectively. Also, this study reports the results of an investigation into the factors which can assess the insulation condition of generator stator winding. Furthermore, a new parameter, Partial Discharge Index(PDI), is introduced as the valuable parameter for the assessment of insulation condition. The ratio between partial discharge increment and the stepwise voltage increment from the Discharge Inception Voltage (DIV) at the characteristic or resonant frequency band shows the close relationship between the breakdown voltage and PDI.

• 한국전기전자재료학회논문지
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• 제15권1호
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• pp.93-101
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• 2002

In this study, the stator form-winding sample coils based on silicone resin and polyimide were made for fault prediction and reliability estimation on the C-Class(200$\^{C}$ ) insulation system of traction motors. The complex accelerative degradation was periodically performed during 10 cycles, which was composed of thermal stress, fast rising surge voltage, vibration, water immersion and overvoltage applying. After aging of 10 cycles, the condition diagnosis test such as insulation resistance '||'&'||' polarization index, capacitance '||'&'||' dielectric loss and partial discharge properties were investigated in the temperature range of 20 ∼ 160$\^{C}$. Relationship among condition diagnosis tests was analyzed to find a dominative degradation factor and an insulation state at end-life point.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.1025-1027
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• 1999

Recently, many researches on a diagnosis of stator winding insulation of large generators are reported. They mostly utilize a trend analysis of Partial Discharge (PD). In this paper, a novel on-line monitoring system for an insulation diagnosis is proposed. This system obtains the parameters such as Maximum Partial Discharge Magnitude (QM), Normalized Quantity Number (NQN) and Dynamic Stagnation Voltage (DSV) by continuous on-line monitoring of winding insulation. It is capable of diagnosing the insulation condition by analyzing the trend of PD and utilizing the database built by the system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1939-1941
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• 2000

Nondestructive and destructuve insulation tests were performed the high voltage rotating machine in the local thermal power plants. Nondestructive tests include measurements of insulation resistance. polarization index, AC current. tan$\delta$, partial discharge. Destructive tests include measurements of AC hipot and DC hipot. This paper propose to establish the insulation diagnosis cycle for high voltage rotating machine.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.584-587
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• 1993

Mica, which have a good thermal and electrical characteristics, while will cleave easily at these layers. In order to bond mica materials soldily, mica/epoxy composite insulation materials were developed for generator stator winding. There are lots of problems such as delamination and partial discharge of these insulation materials caused by mechanical, electrical and thermal aging. Several experiments have been conducted in order to find the useful diagnostic parameters from the partial discharge phenomena by applying a new measurement techniques. this paper deals with the partial discharge pulse characteristics, which may be a useful diagnostic concept in predicting insulation condition of generator stator insulation materials. Long term insulation aging test shows that partial discharge phase angle an magnitude are identified as one of the main key techniques for insulation diagnosis on generator stator winding.

• 사물인터넷융복합논문지
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• 제7권3호
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• pp.9-14
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• 2021

본 논문에서는 주택이나 건물의 단열 진단을 통하여 에너지 손실 요인을 발견하고 이에 따른 에너지 효율 개선에 대한 방향을 제시하고 있다. 건축물의 에너지 효율 요소는 단열 진단, 열교 진단, 창호 진단, 기밀 진단, 설비 진단 등으로 구성된다. 에너지 복지 사각지대 주민 및 시설 중 전라남도 나주시에 위치한 한 경로당 건물을 대상으로 하여 에너지 효율 진단을 실시하고 단열 시공을 한 후의 에너지 효율 진단을 실시하였다. 에너지 측정과 진단 및 분석은 IoT 기반 통합 유무선 에너지 진단 플랫폼인 에너지 파인더를 이용하였다. 비교 결과 전체적으로 16.38%의 에너지 절감률을 달성하였다. 연간 단위 면적당 난방 에너지 소요량은 시공 전 333.51kWh에서 시공 후 277.35kWh로 감소되었고, 연간 단위 면적당 냉방 에너지 소요량은 시공 전 5.51kWh에서 시공 후 5.22kWh로 감소되었다. 연간 단위 면적당 1차 에너지 소요량은 시공 전 464.52kWh 였으나 시공 후 403.69kWh로 감소되었으며, 연간 에너지 사용 비용은 시공 전 3,063,307.14원이었으나 시공 후 2,641,072.49원으로 절감되었다. 단열 이외의 에너지 효율에 영향을 미치는 기준들에 대한 추가적인 개선 작업이 필요하다고 판단된다.