The acoustic noise behavior of transformers under higher harmonic component superposed excitation conditions was analyzed by the corresponding magnetostriction waveform variations. The magnetostriction acceleration level calculated from the magnetostriction waveform well corresponded to the acoustic noise variation for the step-lap type transformer core. For the prediction of transformer noise from alternate-lap core the magnetostriction data was not enough. This suggests that local flux density concentration near the joining structure should be taken into account.
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