Applied Chemistry for Engineering (공업화학)

The Korean Society of Industrial and Engineering Chemistry (한국공업화학회)
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Oxidation Characteristic Changes in Insulation Oil Depending upon Storage Environments and Oil Resources

저장 환경 및 원료에 따른 전기절연유 산화특성 연구

  • Lee, Don-Min (Petroleum Technology R&D Center, Korea Petroleum Quality & Distribution Authority) ;
  • Park, Cheon-Kyu (Petroleum Technology R&D Center, Korea Petroleum Quality & Distribution Authority) ;
  • Ha, Jong-Han (Petroleum Technology R&D Center, Korea Petroleum Quality & Distribution Authority) ;
  • Lee, Bong-Hee (Dept. of Chemical Engineering, Chungbuk National University)
  • 이돈민 (한국석유관리원 석유기술연구소) ;
  • 박천규 (한국석유관리원 석유기술연구소) ;
  • 하종한 (한국석유관리원 석유기술연구소) ;
  • 이봉희 (충북대학교 공과대학 화학공학과)
  • Received : 2016.07.15
  • Accepted : 2016.08.12
  • Published : 2016.10.10
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Abstract

Mineral oil has been widely used as an insulating oil for electrical transformers for a long time, but the necessity of employing new insulation oil such as vegetable oil has been increased due to urgent needs for the biodegradability when it leaks and also for the thermal stability at a higher operation temperature. Although specific periods are required between the production and consumption, there are still short of the data to prove the insulation oils' storage stability depending upon various circumstances and their resources. Thus, this paper demonstrates the insulation oils' oxidation characteristics of both mineral and vegetable oils when each was exposed to different environments for 12 weeks. From this test, some properties including total acid number, water content and dielectric breakdown were changed under specific conditions and resources. Vegetable oils showed higher hydrophilicity and water saturation than those of mineral oils due to their molecular compositions. Under sunlight exposure condition, all insulation oils oxidized and changed their properties when exposing to the direct light, regardless of the resource used.

현재 사용되고 있는 전력 변압기의 절연유는 오랫동안 광유계에서 사용하였으나 최근 절연유 유출에 따른 환경오염인식 증가와 기존보다 고온 운전 조건에서도 절연성능 유지 필요성이 증가하면서 식물계 원료를 이용한 식물성 절연유의 사용이 검토되고 있다. 그러나 제품 특성상 생산 후 사용까지 일정기간 소요될 수 있음에도 불구하고 저장 환경에 의한 제품 변화의 연구는 아직 부족한 상황이다. 본 연구에서는 다양한 환경에서 광유계 절연유와 식물성 절연유를 노출 시킨 후 12주간 주요 물성 분석을 통해 원료별, 환경 조건별 절연유의 산화특성을 비교 검토하였다. 이 과정에서 전산가, 수분함량 그리고 절연파괴전압과 같은 항목에서 원료별 저장환경별 물성변화가 측정되었다. 식물성 절연유의 경우 분자 구조적 특징으로 광유계 절연유와 비교하여 수분함량이 증가하는 경향이 나타났으나 자체의 높은 수분 포화력으로 절연성능에는 지장이 없는 것으로 나타났다. 저장환경에서는 원료에 관계없이 외부 환경에서 일광조사에 의한 절연유의 광분해가가 나타났고 이에 따른 다양한 물성 변화도 측정되었다.

Keywords

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