What is Magnetostriction and its effect on electrical transformer?

Magnetostriction is a phenomenon in which a material undergoes mechanical deformation in response to changes in its magnetic properties. Specifically, when a magnetic field is applied to a magnetostrictive material, it experiences a change in shape or dimensions. This effect occurs due to the reorientation of magnetic domains within the material, leading to the expansion or contraction of the material.

In electrical transformers, magnetostriction plays a significant role in influencing the performance and efficiency of these devices. Transformers consist of a magnetic core made from materials exhibiting magnetostrictive properties. The core is subjected to alternating magnetic fields as part of the transformer’s operation, resulting in cyclic magnetization and demagnetization.

The magnetostrictive deformation of the transformer core introduces mechanical stresses in the material. These stresses can lead to the production of audible vibrations or mechanical noise, which is the main reason for buzzing or humming noise in transformer.This audible hum is a normal consequence of the transformer’s functioning and is more noticeable in transformers that operate at higher frequencies. The intensity of the sound can vary depending on factors such as the transformer’s design, construction materials, and the level of electrical load it is experiencing.

Also, not just noise, the magnetostriction-induced mechanical stresses can contribute to the wear and tear of the transformer core over time. This wear may eventually result in the deterioration of the transformer’s performance and lifespan. Therefore, engineers and designers often take into account the magnetostrictive properties of core materials when selecting and designing transformers, aiming to minimize the undesirable effects of magnetostriction.

Refer: How to minimize magnetostriction in electrical transformers?

To put it briefly, magnetostriction is a phenomenon that causes mechanical deformation in response to changes in the magnetic properties of a material. In electrical transformers, this effect can lead to mechanical noise and stress in the transformer core, influencing its performance and longevity. Careful consideration of magnetostrictive properties is crucial in the design and selection of transformer materials to mitigate potential drawbacks associated with this phenomenon.