A power transformer is one of the most critical and expensive assets in electric systems. Failure a would not only result downtime to entire transmission distribution networks but may also cause personnel environmental hazards due oil leak fire. Hence, enhance transformer’s reliability extend its lifespan, cost-effective reliable condition monitoring technique should be adopted from day install...

This paper studied the impact of moisture on the correlated characteristics of the condenser bushings oil-paper insulation system. The oil-impregnated paper samples underwent accelerated thermal aging at 130 ̋C after preparation at different initial moisture contents (1%, 3%, 5% and 7%). All the samples were extracted periodically for the measurement of the moisture content, the degree of polym...

The paper focuses on corrosion phenomena involving copper, corrosive sulphur and solid insulation of oil-immersed transformers. A study of the available mitigation technique such as passivation to reduce the effects of corrosion phenomena is carried out with the commercially available passivator, Irgamet 39 (Toluiltriazole dialkylamine) (ciba), with concentration of 100 ppm. The paper insulated...

Due to the relatively large availability and reduced price, the mineral transformer oils are widely used as electrical insulating liquids. However, mineral oil drastically degrades over time in service. New efforts were made to improve mineral oils characteristics, and other types of liquids like vegetal oils are proposed. This paper deals with new comparative tests on mineral and vegetal oils ...

This article deals with the gases dissolved in oil generated during the power transformer operation. The attention is paid to the production of gases typical for particular failures. The most powerful and widely used diagnostic tool for investigation faults and their root causes is dissolved gas-in-oil analysis DGA. Hydran sensor is one of the most used sensors applied for on-line monitoring of...