Influencing Factors of Noise Generation in Transformers

Abstract

Noise pollution is an important issue in modern societies. Power transformers are a significant contributor to this unwanted ambient noise. It is therefore desirable to optimize the acoustic behavior of power transformers, i.e. either to minimize the level of noise radiation or to optimize its characteristics in order to lower the level of disturbance for humans. The performance of a transformer core may be considered in terms of power loss and by the noise generated. It is important to ensure that the core loss is low by using an optimum core material and an optimum core fabrication technique. This paper discussed about influencing factors for noise generation like Flux density, core construction, core construction, Building Factor, Core clamping & Pressure, winding diameter, cooling fans and etc. Core vibration is the main factor in the no-load sound level. Flux density, core material, core geometry and waveform of the excitation voltage are the factors that influence the magnitude and frequency components of the transformer core sound levels. Sound level also depends on magnetic property of transformer core material. Factors such as sheet thickness, stress, coatings, induction level and frequency of magnetization affect the magnetic properties of the core material.