A new frequency response analysis method for power transformers

A novel frequency response analysis (FRA) method is described which is being used on power transformers at the KEMA laboratories. This frequency domain method is applied to digitally recorded time signals, is easy to use, and provides high-resolution frequency spectra for both magnitude and phase. This tailor-made FRA method uses a low voltage special impulse source to avoid aliasing. Results from several measured transformers are presented. >