Question

Consider a 10 KVA, 2000/200 V, single phase transformer having below following parameters are r1=10Ω, r2=0.1Ω, l1 = 40mH, l2=0.4 mH, M = 10H. Then the expected primary self inductance will be?

(a) 100.04H

(b) 99.06H

(c) 1.0004H

(d) 10.04H

This question was addressed to me in class test.

This interesting question is from Transformer as a Magnetically Coupled Circuit topic in chapter Transformers of Electrical Machines

Answer 1

Correct choice is (a) 100.04H

Easiest explanation: Primary self inductance = L1 = Lm1 + l1

                                     = (N1/N2)*M + l1

      = 2000/200*10 + 0.04

     =100.04 H.