• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.317-320
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• 1997

The paper reports on a study of the influence of the size of the particles of alumina trihydrate(ATH) filler on the surface aging characteristics of ehylene propylene diene terpolymer(EPDM). A fixed 100pph concentration of the filler of ATH was used (or all particle sizes from 0.7 to 20$\mu\textrm{m}$, It is show that hysteresis of contact angle and leakage current increase with increasing particle size, whereas tracking resistance decrease with increasing particle size.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1673-1675
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• 1996

We have studied the effect of surface tension and flow rate of contaminants, wettability, frequency of applied voltage dependence of tracking breakdown. As the flow rate of contaminant is increasd, the surface resistivity is decreased, and the leakage current is increased, the time to tracking breakdown is decreased. It is found that time to tracking breakdown depends on the frequency of contaminant, that is difference of wettability. And as the frequency of applied voltage is increased, time to tracking breakdown decreased.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.266-269
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• 2001

This paper investigated the aging characteristic under long-term corona discharge on roan temperature vulcanized silicone rubber, which has been using as a protective coating material for solving the contaminant problem. The applied electrical field is 10kV/cm ac and corona discharge treatment was applied on RTV silicone rubber sheet for maximum 250 hours. With the duration of corona discharge. the diffusible low molecular weight species increased, which was determined the usage of n-hexane extraction method. In addition, the contaminant layer was formed on the treated surface, and then measured the contact angle. We investigated the relation of contact angle and diffusible low molecular weight species. It is found that scissor of main chain PDMS and side chains $(CH_3)$ and the generation of LMW species were occurred by a corona discharge. The improvement of hydrophobicity rate is thought due to the increase of diffusible LMW species.

• E2M - 전기 전자와 첨단 소재
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• 제10권8호
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• pp.770-777
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• 1997

Some polymer materials including epoxy resin are being instead of porcelain for outdoor insulating materials such as insulators bushings cable terminators and surge arrester housing. And the largest problem to be overcomed is the tracking and erosion of the outdoor polymer material brought about by dry band arcing during prolonged exposure to contaminations. In this paper the effect of surface tension wettability flow rate of contaminants with varying surfactant content and frequency of applied voltage on the tracking breakdown of epoxy insulating materials were investigated. As the flow rate of contaminant is increased the surface resistivity is decreased and the leakage current is increased the time to tracking breakdown is decreased. It is found that time to tracking breakdown depends on the surface tension of contaminant that is difference of wettability. And as the frequency of applied voltage is increased time to tracking breakdown decreased.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.266-269
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• 2001

This paper investigated the aging characteristic under long-term corona discharge on loon temperature vulcanized silicone rubber, which has been using as a protective coating material for solving the contaminant problem. The applied electrical field is 10kV/cm ac and corona discharge treatment was applied on RTV silicone rubber sheet for maximum 250 hours. With the duration of corona discharge, the diffusible low molecular weight species increased, which was determined the usage of n-hexane extraction method. In addition, the contaminant layer was formed on the treated surface, and then measured the contact angle. We investigated the relation of contact angle and diffusible low molecular weight species. It is found that scissor of main chain PDMS and side chains (CH$_3$) and the generation of LMW species were occurred by a corona discharge. The improvement of hydrophobicity rate is thought due to the increase of diffusible LMW species.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.501-504
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• 1997

We investigated the tracking and erosion resistance of the silicone rubber by Inclined-Plane Method. And. with the variation of experiment time, the chance of the leakage current waveform was evaluated. The typical leakage current waveform was the form of mixture of sinusoidal wave and rectifying wave. It is thought that the sinusoidal wave is due to conductivity of contaminant when wet. and the rectifying wave is due to arc of dry band.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.1121-1124
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• 2004

Aging test to estimate life property of polymer insulator is executed through several international standard such as IEC 61109 and CEA tracking wheel test, but is not getting clear conclusion yet. There are two methods in the diagnosis method of polymer insulator such as off-line and on-line. The diagnosis methods in off-line are external condition analysis by the eye, contaminant analysis on surface, surface analysis, pollution withstand voltage test, power frequency flashover voltage test, lightning impulse flashover test, tensile fracture load test and flexural load test. The diagnosis methods in off-line most are the method for virgin and last aged sample. However, the diagnosis method in on-line is method that can be evaluate sample state as progressing continuously aging test in beginning, The diagnosis method in on-line is arranged as following: leakage current measurement, electric field, surface state investigation, thermal image, emitting light measurement and then so. In this paper, the tracking performance of polymer insulator with salt solution which is added surface active agent. The diagnosis of insulator sample has been analyzed by leakage current and visual examination.

• Journal of Electrical Engineering and Technology
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• 제10권1호
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• pp.299-307
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• 2015

Reduction in pollution performance of polymeric insulators, aged due to water absorption stress and thermal stress, is a major threat to the reliable operation of power transmission and distribution system. Formation of partial discharges on the surface of wet polluted insulator plays a major role in determining the life time and pollution performance of outdoor polymeric insulators. However, reports on partial discharge characteristics of water absorption stress aged and thermal aged polymeric insulators are scanty. This paper discusses the pollution performance characteristics of accelerated aged polymeric insulators using the advanced ultra wide band PD signal measurement and analysis. Laboratory experiments on accelerated aged polymeric insulators were carried out as per IEC 60507 under AC voltage, at different humidity and contamination levels using NaCl as a contaminant. PRPD pattern and Time-Frequency map analysis of PD signals were carried out. From the results, it can be speculated that PD analysis is a well suited technique to understand the pollution performance of aged polymeric insulators.

• 한국지하수토양환경학회지:지하수토양환경
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• 제12권1호
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• pp.1-35
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• 2007

지난 수십년 동안 토양내 수착된 오염물질이 접촉시간(contact time)이 경과함에 따라 생물학적 또는 화학적 이용성의 감소는 일반적으로 인식되어 오고 있다. 이와 같은 aging 또는 격리(sequestration)라 불리는 현상이 위해성에 직접적인 영향을 미친다는 것이 알려져 있다. 이러한 현상은 소수성 오염물질을 중심으로 보고되어 왔으나, 최근 연구결과에 의하면 중금속의 경우에도 이와 같은 현상이 발견되고 있으며, 이는 오염물질의 흡-탈착 이력(hysteresis) 현상, 비가역 흡착, 탈착저항성, 비평형 흡착 등과 직접적으로 연관된 것으로 알려지고 있다. Aging 또는 sequestration에 의한 오염물질의 생이용성(bioavailability)의 감소는 인체에 대한 실질적인 위해성의 감소를 의미한다. 최근 들어 이와 같은 과학적인 증거를 토대로 단순한 오염물질의 농도 측정이 아니라 위해성에 근거한 오염 복원(또는 관리)의 개념이 도입되어 환경친화적인 복원수준의 선정에 적용하고 있다. 이는 토양내 오염물질의 총농도가 아니라 오염물질의 생이용성 또는 독성을 기준으로 하여 정화수준을 결정함으로써 오염부지의 처리비용과 노력의 절감효과를 동시에 기대할 수 있기 때문이다. 토양내 잔류오염물질의 생이용성 또는 독성은 오염물질의 이동 또는 거동 특성에 의해 영향을 받으며 결국 생물체로의 노출 경로와 생체축적에 직접적인 영향을 미친다. 본 논문에서는 토양내 오염물질의 위해성을 평가하여 토양오염복원에 적용시 과학적인 타당성에 대해 살펴보고자 하였다.

• 유기물자원화
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• 제10권2호
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• pp.132-139
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• 2002

본 연구는 디젤의 오염기간 및 토성이 콤포스팅 처리효율에 미치는 영향을 살펴보고자 실시하였다. 오염경과기간은 15일과 60일로 하였으며 대조실험으로 오염직후의 토양실험도 실시하였다. 연구에 사용된 토양은 실트질양토와 사토이었으며 대상오염물질은 디젤오일이었다. 초기오염농도는 건조질량기준으로 약 10,000mgTPH/kg으로 하였으며, 수분은 각 토성의 수분보유능력의 70%로 조절하였다. 유기물질 보충 및 미생물식종의 목적으로 하수슬러지를 첨가하였으며 토양대 슬러지 혼합비율은 습윤질량비로 1:0.3이었다. 휘발된 TPH양은 초기농도의 0.9-1.8%정도로써 디젤오염토양의 콤포스팅 적용시 디젤은 주로 생물학적인 요인에 의하여 제거되었다. 휘발에 의하여 손실되는 n-alkanes들은 대부분 C10~C17의 성분들이었으며, 특히 C10~C14까지의 성분들이 C15 이상의 성분들보다 휘발이 많이 되었다. 사토의 TPH에 대한 1차반응 분해속도상수 k값은 0.081-0.094/day로 실트질양토의 0.056-0.061/day보다 약 1.5배 정도 높았다. 오염경과기간의 영향을 살펴보면, 60일까지의 오염경과기간으로는 TPH 분해효율의 뚜렷한 차이를 발견할 수 없었다. 이산화탄소회수율은 0.61-0.89이었으며, TPH분해량과 이산화탄소발생량과의 상관계수는 0.90-0.96의 범위에 있었다.