Frequency response analysis for power transformer

Abstract

This paper presents an analysis of transformer faults to determine the damage occurring within the transformer by the frequency response analysis (FRA) method. Enter the frequency from 10 Hz to 3 MHz, and then the measured value is compared to the standard reference value. Consider the different graphs of frequency response in various frequency ranges to analyze the deformation of the iron cores and transformer coils to know the internal condition of the transformer. The tests show that the 50 MVA 115 kV/22 kV transformer has severe damage to the high voltage side and low voltage side of phase-A coil. As a result, the transformer can not be used in the power system, and make a reminder to repair the transformer.