Prediction of hot-spot and top-oil temperatures of power transformers according to IEEE standards C57.110-1998 and C57.91-1995

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2007
Karaca, Haldun
In this thesis, the effects of Harmonics on the Top Oil and Hot Spot Temperatures of Power Transformers used in Turkish Electricity Transmission System have been investigated. Due to the solid state equipment, the harmonic levels increase. This effect raises the losses and temperatures in the transformer windings. None of the power transformers currently used in Turkey has measuring equipment suitable for measuring the Hot-Spot temperatures. In this study, a computer program is written in LABVIEW which measures the harmonics and calculates the temperatures in accordance with the methods recommended in IEEE Standards C57.110-1998 and C57.91-1995. Also for sample transformers the work has been verified by measuring the Top-Oil temperatures of the transformers and then comparing with the calculated results.

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Citation Formats
H. Karaca, “Prediction of hot-spot and top-oil temperatures of power transformers according to IEEE standards C57.110-1998 and C57.91-1995,” M.S. - Master of Science, Middle East Technical University, 2007.