Purpose of lamination in a transformer core

A transformer core is made of iron, which is a good conductor. When the magnetic flux through the core changes with alternating current, it can induce circulating currents inside the core itself. These are called eddy currents.

Why eddy currents are undesirable

Eddy currents produce heating in the core, leading to energy loss.

The power loss due to eddy currents is reduced if the conducting path inside the core is broken into thin insulated sheets.

Role of lamination

Laminating the core means making it from many thin insulated iron sheets instead of one solid block.

This increases the resistance to circulating eddy currents and hence reduces the eddy current loss.

Check the options

• A: reduce the energy loss due to eddy currents — Correct.
• B: make it light weight — Not the main reason.
• C: make it robust and strong — Not the purpose of lamination.
• D: increase the secondary voltage — Secondary voltage depends on turns ratio, not lamination.

Final answer

Therefore, the transformer core is laminated to reduce energy loss due to eddy currents.