Dissolved gas analysis (DGA) of arcing faults in biodegradable oil insulation systems

Due to environmental concerns regarding the use of mineral oil, biodegradable oil was commercially introduced as an alternative for transformer insulation in 1999. Since then, the usage of this oil in the power industry has steadily increased and a lot of researches have been in progress to make biodegradable oil as compatible as mineral oil. This paper presents results of experimental tests performed on laboratory models of transformer windings immersed in biodegradable oil. The experiment involved an investigation of hydrocarbon gas products generated when arcing happened. The aim is to determine whether analysis based on existing DGA fault interpretation methods which were developed for mineral oil need to be modified when applied to insulation assessment of biodegradable oil.