APPLICATIONS OF NATURAL ESTERS ALTERNATIVE TO MINERAL OILS IN POWER TRANSFORMERS

Öz

The electrical and environmental disadvantages of mineral oils, traditionally used as insulating fluids in power systems, lead to the search for alternatives. Natural esters produced from vegetable seeds are one of the most important alternatives. Natural esters with high dielectric strength can meet ultra-high voltage transformer design requirements. In addition, they can respond to environmental concerns caused by transformer oils with their biodegradability. This study first compares natural esters with other trans-former oils and explains why natural esters stand out. The basic properties of natural esters are defined in terms of advantages and disadvantages, and power system applications are exemplified. Esterification and synthesis of nanoparticle-added nanofluids, widely used in the literature to improve natural esters' electrical and thermal properties, are presented with experimental applications. Natural esters can have a better oxidation stability with the esterification process. The AC, DC, and lightning impulse (LI) break-down voltages of nanofluids based on natural esters also enhanced by 10% on average. This substation and experimental applications in which natural esters are used show that these environmentally friendly oils can provide insulation requirements in many power system equipment, especially transformers.

Anahtar Kelimeler

• Transformer Oils
• Power Transformers
• Liquid Dielectrics

Destekleyen Kurum

The Scientific and Technological Research Council of Turkey (TUBITAK)

GÜÇ TRANSFORMATÖRLERİNDE MİNERAL YAĞLARA ALTERNATİF DOĞAL ESTERLERİN UYGULAMALARI

Öz

Geleneksel olarak güç sistemlerinde yalıtım sıvısı olarak kullanılan mineral yağların elektriksel ve çevresel dezavantajları alternatif arayışlara neden olmaktadır. Bitkisel tohumlarından üretilen doğal esterler bu mineral yağlara en önemli alternatiflerden biridir. Yüksek dielektrik dayanıma sahip doğal esterler, ultra yüksek gerilim transformatörü tasarımının gereksinimlerini karşılayabilmektedir. Ayrıca doğada çözünebilirliği sayesinde transformatör yağlarının neden olduğu çevresel kaygılara da cevap verebilmektedirler. Bu çalışma öncelikle doğal esterleri diğer transformatör yağlarıyla karşılaştırmakta ve doğal esterlerin sıvı yalıtkanlar arasında öne çıkma nedenlerini açıklamaktadır. Doğal esterlerin temel özellikleri avantaj ve dezavantajları açısından tanımlanmakta ve güç sistemi uygulamaları örnekleri sunulmaktadır. Doğal esterlerin elektriksel ve termal özelliklerinin iyileştirilmesi amacıyla literatürde yaygın olarak kullanılan nano-parçacık katkılı nano-akışkanların esterleştirilmesi ve sentezi deneysel uygulamalarla sunulmaktadır. Doğal esterler, esterleştirme işlemiyle daha iyi bir oksidasyon kararlılığına sahip olabilmektedir. Doğal esterlerle üretilen nano-akışkanların AC, DC ve yıldırım darbesi (LI) delinme gerilimleri de ortalama %10 artmaktadır. Doğal esterlerin kullanıldığı bu şalt sahası ve deneysel uygulamalar, çevre dostu bu yağların, başta transformatörler olmak üzere birçok güç sistemi ekipmanında yalıtım ihtiyacını karşılayabildiğini göstermektedir.

Anahtar Kelimeler

• Transformatör Yağları
• Güç Transformatörleri
• Sıvı Yalıtkanlar

Kaynakça

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