The criteria of dissolved gas analysis in natural ester fluid

Abstract

In this paper, dissolved gasses of natural ester fluid were analyzed to suggest DGA criteria for transformer filled with natural ester fluid. Samples of mineral oil and natural ester fluid made to correspond to the ratios of the iron core, winding, insulating materials and insulating oil in a transformer were deteriorated for 1,600 hours in a 150 thermostat and samples were collected every two hundred hours to analyze changes in the contents of dissolved gases. As the results, H 2 and C 2 H 2 gases were hardly detected and C 2 H 6 gas detected from natural ester fluid was two times larger in quantity than mineral oil. CH 4 gas detected from natural ester fluid was 1/4 in quantity of the gas detected from mineral oil. Amount of other dissolved gasses were similar to each other. Based on these results, DGA criteria for transformers applied with natural ester fluid were presented.

Dissolved gas analysis differences between natural esters and mineral oils used in power transformers: a review

“…In [57], five generated gases (H 2 , CH 4 , C 2 H 4 , C 2 H 6 , C 2 H 2 ) in mineral oil and natural ester under thermal stress with and without added transformer materials were compared. Both oils were deteriorated for 1600 h at 150°C and collected every 200 h to analyse changes in the contents of dissolved gases.…”

Gassing Tendency of Fresh and Aged Mineral Oil and Ester Fluids under Electrical and Thermal Fault Conditions

“…It was reported that the condition (age) of the oil has a significant influence on the concentration of the dissolved gases which affects the fault diagnostic conditions. Also, the influence of thermal aging on the gassing tendency of mineral oil and natural esters under the influence of thermal faults has been reported in [19]. A significant change in the dissolved gas concentration has been noticed with an increase in the thermal aging duration of the dielectric fluids.…”

“…However, a large amount of C 2 H 2 is generated as compared to the low energy discharge cases. The gassing tendency of ester fluids under thermal faulty condition was also investigated and are reported in [14,15,[18][19][20]. It is found that natural ester generates more gases at a higher temperature (>300 • C) and traces of C 2 H 6 are found increasing with increasing temperature.…”