Question

What is the formula for the width of the window of the transformer?

(a) width of the window = distance between core centers + diameter of the circumscribing circle

(b) width of the window = distance between core centers – diameter of the circumscribing circle

(c) width of the window = distance between core centers * diameter of the circumscribing circle

(d) width of the window = distance between core centers / diameter of the circumscribing circle

This question was addressed to me in an interview for internship.

The query is from Overall Dimensions topic in division Design of Transformers of Design of Electrical Machines

Answer 1

Correct choice is (b) width of the window = distance between core centers – diameter of the circumscribing circle

Best explanation: The diameter of the circumscribing circle is obtained from the formula, diameter of the circumscribing circle = square root of ratio of cross sectional area of the core to the space factor. After obtaining the distance between core centers, the width of the window is obtained.