Experimental Study of Testing Models for Low Noise Amorphous Alloy Core Power Transformers

Although the amorphous alloy core power transformers have the advantage of lower core loss, the high noise level and weak short-circuit strength are inevitable. To explore the countermeasures for noise decreasing, an amorphous alloy core model was employed for detailed experimental study. A large number of noise measurements (A-weighted sound pressure level) were implemented by changing magnetic flux density of amorphous alloy core, and the probability distribution of the noise was obtained and the variations of the noise with the magnetic flux density were figured out. Noise measurements were carried out by changing the arrangements of the core vertically or horizontally, and the testing was carried out by fixing the magnetic flux density at 1.25 T. Noises were also measured at various clamping forces of the amorphous alloy core model. All above testing results are very helpful for optimizing design and improving manufacture technologies for the amorphous alloy core power transformers.