trafovähendus

Trafovähendus, also known as transformer noise reduction or transformer hum attenuation, refers to methods and technologies employed to minimize the audible noise produced by electrical transformers. This noise, often a low-frequency hum, is primarily generated by the magnetostriction of the transformer's core material and by the electromagnetic vibrations of the windings.

The primary source of transformer noise is magnetostriction, a phenomenon where ferromagnetic materials change shape slightly when subjected to a magnetic field. As the alternating current flows through the transformer's windings, the core is repeatedly magnetized and demagnetized, causing it to vibrate. These vibrations are transmitted to the surrounding air, creating the characteristic hum. Mechanical vibrations from the cooling fans and the enclosure can also contribute to the overall noise level.

Various techniques are used to reduce trafovähendus. These include designing transformers with optimized core laminations to minimize magnetostriction, using advanced core materials, and employing acoustic enclosures or barriers to absorb or block the sound waves. Damping materials can be applied to the transformer's tank and internal components to reduce vibration transmission. The mounting of the transformer also plays a role, with vibration isolation systems being used to prevent the transfer of vibrations to the building structure. In some cases, active noise cancellation technologies can be employed, though this is less common for typical power transformers.

The need for trafovähendus is driven by environmental regulations, public health concerns, and the desire for quieter operation, especially in residential areas or noise-sensitive environments like hospitals and schools. Effective noise reduction contributes to improved quality of life and can prevent noise pollution.