Hydrocarbon gases dissolved in palm-based insulation oil after experienced breakdown

Oil-filled transformer is widely used in power system network. Its dielectric system consists of solid and liquid dielectric. There are different types of liquid dielectric to choose for transformer used such as mineral oil and ester based oil. Mineral oil has been used commonly since the earlier production of oil-filled transformer, while ester based oil is plant based oil that has been introduced afterwards to overcome the deficiency of mineral oil such as non-biodegradable, low fire point, and limited resource. Palm Fatty Acid Ester (PFAE) is one of ester based oil produced from palm oil. Past studies claimed that PFAE has 0.6 times less viscosity and 1.3 times higher dielectric constant compared to mineral oil. This paper focuses on comparing hydrocarbon gases dissolved in mineral oil and PFAE after AC breakdown test. Dissolved gas-in-oil analysis (DGA) technique is used to determine the concentration of hydrocarbon gases dissolved in each samples before and after breakdown test. The breakdown test was conducted according to IEC 60156. The outcome shows that the two samples have different gases concentration when experienced breakdown faults. The generated gases pattern and the DGA interpretation results for both samples will be discussed further in this paper.