Question

What is the condition for minimum loss condition?

(a) current density in primary < current density in secondary

(b) current density in primary > current density in secondary

(c) current density in primary = current density in secondary

(d) current density in primary >= current density in secondary

I had been asked this question in an international level competition.

This interesting question is from Design of Core and Winding topic in section Design of Transformers of Design of Electrical Machines

Answer 1

Right answer is (c) current density in primary = current density in secondary

For explanation I would say: The condition for the minimum loss should be the current density in primary should be equal to the current density in secondary. Any different condition, could lead to high amount of loss.