Question

What is the relation between the overhang specific permeance and the slot pitch?

(a) overhang specific permeance is directly proportional to the slot pitch

(b) overhang specific permeance is indirectly proportional to the slot pitch

(c) overhang specific permeance is directly proportional to the square of the slot pitch

(d) overhang specific permeance is indirectly proportional to the square of the slot pitch

I have been asked this question in an interview for internship.

This intriguing question comes from Pulsation Losses & Types of Leakages in chapter Principles of Magnetic Circuit Design of Design of Electrical Machines

Answer 1

Correct choice is (b) overhang specific permeance is indirectly proportional to the slot pitch

For explanation I would say: The overhang specific permeance relation obtained is an empirical relation. In the empirical relation, the overhang specific permeance is indirectly proportional to the slot pitch.