Eddy Current Loss in a transformer is directly proportional to

Eddy Current Loss in a transformer is directly proportional to which of the following factors:

1. The supply frequency
2. The flux density in the core
3. The thickness of core lamination
4. Square of the thickness of core lamination

Correct answer: 4. Square of thickness of core lamination

Explanation: A time-changing flux induces voltage within a ferromagnetic core. Swirls of current are associated with these voltages, swirls of current begin to flow within the core. The shape of these current swirls is like eddies seen in rivers. Thus the name eddy current is given. The eddy current losses are directly proportional to the square of laminations thickness. For this reason, the laminations are designed as thin as possible.