Experiments and New Mathematical Models for Prediction of Transformer Oil Characteristics under Environment Pressure Stress
Subject Areas : electrical and computer engineering
Mohammad
Mirzaie
1
(University of Science and Technology)
Ahmad
Gholami
2
(University of Science and Technology)
H. R.
Tayebi
3
Keywords: Mineral oilair pressureinsulationmodeling,
Abstract :
Mineral oil in transformer is used for its insulation property and thermal transfer to external environment. Transformer oil is always under air pressure variation effects due to contact to external by silica gel chamber and the pressure which depends on the height of sea level. Therefore air pressure can affect on insulation parameters and its age. Air pressure changing can cause oil viscosity variation. In this paper, the air pressure effects on oil properties are studied by the use of tests carried out and measuring of the insulation characteristics. In a laboratory environment, air pressure was changed from 40 to 1250 mmHg using a pump. Then conductivity/leakage current and breakdown voltage are measured and analyzed. These results are used to presenting estimation models and also for suggestion of a new simple model by mathematical methods and then the models were compared to each other.
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