Question

What is the formula for the height of length of mean turn of armature?

(a) length of mean turn = 2*length + 2.5*pole pitch + 0.06 kV + 0.2

(b) length of mean turn = 2*length + 2*pole pitch + 0.06 kV + 0.2

(c) length of mean turn = 2*length + 2.5*pole pitch – 0.06 kV – 0.2

(d) length of mean turn = 2*length – 2.5*pole pitch – 0.06 kV – 0.2

I had been asked this question in semester exam.

This interesting question is from Slot Dimensions topic in division Design of Synchronous Machines of Design of Electrical Machines

Answer 1

Correct choice is (a) length of mean turn = 2*length + 2.5*pole pitch + 0.06 kV + 0.2

Explanation: The length of the slots is obtained along with the pole pitch. The output kV is calculated and on substituting we get the length of mean turn.