Natural ester insulating oil has the advantages of environmental protection

renewable property

high ignition point

high safety

etc. At present

the research on the characteristics of high energy arc discharge at working frequency in natural ester insulating oil is rarely available in the literature. We performed the experiments of high-frequency high-energy arc in different insulating oils with rod-stick electrodes

and compared the differences of arc discharge characteristics between mineral oil and natural ester in terms of arc energy

pressure characteristics

gas production characteristics

and so on. The results show that

under the same arc current and gap distance (5 kA

30 mm)

the arc energy in mineral oil and natural ester is 48.267 kJ and 41.891 kJ

respectively. The arc energy

pressure peak

gas production

gas production rate

bubble surface area

gas production per unit area and average voltage gradient of the natural ester are smaller than those of mineral oil. In the process of arc discharge in oil

arc discharge

insulating oil cracking gas production and bubble pulsation are coupled with each other. The type of insulation oil significantly affects the gas production rate per unit area

which in turn causes the differences in the discharge characteristics. Under the same experimental conditions

the peak pressure generated by arcing in natural ester is 47% lower than that in mineral oil

indicating that the use of natural ester can significantly reduce the pressure rise inside the transformer under arcing faults and improve its explosion-proof capability. In addition

the experimental results of this paper can be further used to guide the parameterization of natural ester transformer gas protection.