کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
644486 | 1457124 | 2016 | 10 صفحه PDF | دانلود رایگان |
• Hot-spot temperatures in vegetable oil are higher than the ones in mineral oil.
• Polymerization degree of Kraft paper in vegetable oil is higher than in mineral oil.
• Poor cooling in vegetable oil could be offset by low degradation rate of paper.
Kraft paper in combination with dielectric oil is the most common as insulation system used in power transformers. The most used oil in power transformers is mineral oil. However, dielectric oils based on natural esters possess some advantages in comparison with mineral oil such as higher biodegradability, fire safety and availability. Therefore, they might be the most ideal substitute for mineral oil. The introduction of a new material requires the evaluation of its degradation rate because this determines transformers’ life span. In order to assess the performance of new insulating systems based on vegetable oils, simulations to obtain the hot-spot temperatures in power transformers using vegetable oils and controlled laboratory experiments of ageing were carried out. The reason is that hot spot temperature inside windings of the oil-immersed power transformers is one of the main manifestations of the thermal stress which leads to aging of insulation systems.
Journal: Applied Thermal Engineering - Volume 104, 5 July 2016, Pages 129–138