A 220V, 15kW,1000rpm shunt motor with armature resistance of 0.25Ω, has a rated line current of 68A and a rated field current of 2.2A. The change in field flux required to obtain a speed of 1600 rpm while drawing a line current of 52.8A and a field current of 1.8A is [GATE2012]

A 220V, 15kW,1000rpm shunt motor with armature resistance of 0.25Ω, h

1.	A 220V, 15kW,1000rpm shunt motor with armature resistance of 0.25Ω, has a rated line current of 68A and a rated field current of 2.2A. The change in field flux required to obtain a speed of 1600 rpm while drawing a line current of 52.8A and a field current of 1.8A is [GATE2012]
A.	18.18% increase
B.	18.18% decrease
C.	36.36% increase
D.	36.36% decrease
Answer» E.