Magnetizing current of a Large Power Transformer and its Harmonic Spectrum in Normal and GIC conditions

Abstract

A measurement of the harmonic spectrum of magnetizing current was performed. This paper analyzes the results of the measurement of harmonic spectrum of magnetizing current in standard noload test at various values of induction. Magnetizing current harmonic spectrum during single-phase noload test was measured as well as the impact of combined AC and DC magnetization on core behavior and harmonic spectrum. A mathematical model of transformer core is introduced. The calculated results are presented.