TRANSFORMER NOISE PERFORMANCE DIAGNOSIS METHOD AND NOISE REDUCTION METHOD

A transformer noise performance diagnosis method comprises: acquiring a frequency spectrum of a noise of a stacked iron core included in a transformer, the stacked iron core being formed by stacking electrical steel sheets; for excitation vibration calculation of the stacked iron core, determining transverse elasticity moduli in two planes each including a stacking direction of the stacked iron core; performing the excitation vibration calculation for the stacked iron core using a constitutive equation that includes an elasticity matrix including the determined transverse elasticity moduli as elements and acquiring a frequency spectrum of an excitation vibration of the stacked iron core; calculating a difference between the spectrum of the excitation noise of the stacked iron core and the frequency spectrum of the excitation vibration of the stacked iron core as a difference spectrum; and diagnosing noise performance of the transformer based on the difference spectrum.