The paper presents a global Finite Element Method model developed to understand and quantify the complex phenomena of energetic transfer and overpressure taking place within a transformer vessel during and after a short-circuit. The goal of the model is to design an efficient system able to protect Power Transformers against explosion and resulting oil fire. The model presentation and compariso...

Dissolved gas analysis (DGA) has been widely applied to diagnose internal faults in transformer insulation systems. However, the accuracy of DGA technique is limited because of the lack of positive correlation of the fault-identifying gases with faults found in power transformers. This paper presents a laboratory study on the correlation between oil dissolved gas formation and partial discharge...

Corrosive sulfur and the effect that it has in transformer systems can be significant. The extent of the corrosion damage caused by sulfur, if left unchecked, can be so severe as to cause failure of the apparatus. The problems with corrosive sulfur have been recognized for quite some time. As early as 1948, F.M. Clark and E.L. Raab [1] issued a report on the subject for method development withi...

Degradation of cellulosic materials can be identified by measuring dissolved carbon oxide gas content in oil, Degree Polymerization (DP) of paper and 2-Furfurol content in oil. Each method has some advantages and limitations. In case of dissolved carbon oxide gas analysis and furan content determination, sampling is easy but interpretation of result is not very reliable. On the other hand DP me...

The benefit of transformer oil seeded with magnetic nanoparticles (forming a oil-based ferrofluid) is numerically studied in an axisymmetric model 40 kVA transformer. maximum temperature the system decreased by 2.2 °C when using ferrofluid instead oil. This effect mainly due to body force, which modifies convective flow and enhances heat transfer. leakage field highly localized limits thermomag...