Evaluación del nivel ruido audible en transformadores de distribución usando el Método de Presión Sonora

Abstract

In this paper the results of audible noise measurements to ten no-load distribution transformers are presented using the sound pressure method. The tests were done in the Audible Noise Laboratory of Universidad del Valle, according to the requirements described in the Colombian Technical Standard NTC 5979. The tests allowed to verify the conformity of the product in respect with the audible noise limits established in the Colombian Technical Standard NCT 5978. In addition, it was possible to identify the effect of noise emissions of two transformers when making variations of voltage in the power source. It was found that the noise level emitted by the transformers under test is considerably lower than the limits established in the standard and it is significantly affected by the voltage of the source supply.

Structure Electromagnetic Force Analysis of WPT System Under Fault Conditions

“…In the formula, Am is the magnetic vector potential near the coupling coil, Bn,j and Bt,j are the normal component and tangential component of magnetic induction strength respectively. Substitute equation (10) into equation (9), the EMF density on the coil unit is:…”

“…In reference [8], the characteristics of EMF considering different types of resonant current are derived, and the multi physical field model of PMSM is established. In reference [9], the phenomenon of transformer vibration caused by EMF is rated by the method of sound pressure. In reference [10], the influence of the material characteristics and geometric structure of the iron core on the stress of the winding of the intermediate frequency transformer is analyzed.…”