Harmonics in Transformer Magnetizing Currents

The purpose of this paper is to show in a concise manner the cause and effects of higher harmonic currents in magnetizing currents of transformers. A hypothetical case is analyzed to show the cause of the harmonics; then the schemes of connecting transformers that are commonly used for polyphase transformation are taken up and the effects of the harmonics on each case pointed out. The author also shows the reason why third-harmonic voltages are not developed in the three-phase ``core type´´ transformer when connected star-star.