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Item type:Item, The Behavior of Dissolved Gas in Mineral Oil with TiO2 and Three Types of Insulation Paper at 150 Degree Celsius(2024-01-01) ;Jongvilaikasem, Korraya ;Bunlaksananusorn, Chanin ;Vittayakorn, WanwilaiPattanadech, NorasageThe main electrical insulation in oil-immersed transformers is liquid insulation and paper insulation. Liquid insulation is generally used mineral oil. However, improvements in the quality of liquid insulation are continually being made for better efficiency i.e. adding various additives such as inhibitors and nanoparticles. Nanoparticles are a solid substance used in research for many years. TiO<inf>2</inf> is a type of nano that is commonly used in research to increase the efficiency of mineral oil. This research experimented by preparing dry transformer oil mixed with 0.03% TiO<inf>2</inf>. The test vessels consisted of 3 main components: 1) 35 ml of MO with 0.03% TiO<inf>2</inf>, 2) 1 gram of paper with three types of insulation including pressboard, kraft, and diamond dot paper, and 3) two types of coils including copper and aluminum with size 1∗2.5 cm. The sample vessels were aged at 150 C for 72 hours in the vacuum oven. After aging, oil samples were analyzed by dissolved gas analysis (DGA). From the DGA test results, it was found that similar weights of different types of paper produced different gas-generating results. - Some of the metrics are blocked by yourconsent settings
Item type:Item, The Behavior of Dissolved Gas in Difference Liquid Insulation With ZnO Under Thermal Ageing Condition(2024-01-01) ;Jongvilaikasem, Korraya ;Bunlaksananusorn, Chanin ;Vittayakorn, WanwilaiPattanadech, NorasageMineral oil is a commercial product that has been widely used as a dielectric liquid in transformers. However, alternative liquids have been developed to gradually replace mineral oil because of some better liquid insulating properties in the point of safety aspect and environmentally friendly. This paper represented the behavior of Dissolved Gas in different types of liquid insulations mixed with nanoparticles under thermal aging conditions. Various types of liquid insulation including mineral oil, natural ester, and palm oil added with a 0.03% concentration of zinc oxide (ZnO) and sorbitan mono-oleate surfactant (Span 80) underwent thermal stress aging at 90, 110, 130, and 150 degrees Celsius with 200 mbar for 72 hours in a vacuum oven. Then, the concentration of dissolved gas in the stressed samples was investigated by the Dissolved Gas Analysis (DGA) technique. From the test results, it was discovered that distinct liquid insulations and aging temperatures produced diverse dissolved gas generation behaviors. Besides, the dielectric liquid with Nanofluids or Nanofluids mixed with span 80 seems to have no different dissolved gas generation behaviors. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Dissolved Gas Analysis of Palm Oil Compared with Mineral Oil from Different Types of Breakdown Voltage(2020-10-25) ;Suksagoolpanya, Suthat ;Jongvilaikasem, Korraya ;Jariyanurat, Kitipod ;Banthoengjai, ThanpilinJeenmuang, SiwakornNatural products are required instead of chemical materials for saving the environment. Nowadays, the palm oil is a new alternative liquid insulation that may be used in a transformer. Normally, the characteristics of liquid insulation can be investigated and analyzed by various methods. One of the diagnosis methods widely used is a dissolved gas analysis technique (DGA). The propose of this paper is to study the interpretation of dissolved gases in the palm oil compared with that of in the mineral oil which is caused by different kinds of breakdown phenomena, i.e. AC breakdown, positive lightning impulse breakdown, and negative lightning impulse breakdown. An AC breakdown voltage test according to IEC 60156 was performed by using 3 difference gap spacing which were 1.0, 1.5, and 2.0 mm. For lightning impulse tests, the test cell was contained needle-sphere electrodes with 10, 15, and 20 mm gap different spacing. The lightning impulse tests were performed in accordance with IEC 60897. Each experiment was performed for 5, 10, and 15 times. For a material preparation, the mineral oil and the palm oil was heated at 80oC for 12 hours. Then, it was naturally cooled before filling into the test cell to perform AC and lightning impulse breakdown tests. After that, the mineral oil and the palm oil was sampled out of the test cell to perform the DGA experiment. The dissolved gases from the mineral oil and the palm oil were interpreted by applying IEC and IEEE gas interpretation techniques. It was found that the breakdown voltages of the palm oil were less than the mineral oil but the palm oil generates more dissolved gases than the mineral oil. Moreover, Duval pentagon for natural ester fluid seemed to be the most suitable method to interpret dissolved gases in the palm oil compared with the IEC ratio, Doernenburg ratio, Roger ratio, and Duval triangle.
