Electrical Machines
The synchronous reactance( Xs) is the

 combined reactance due to armature reaction and leakage flux
 reactance due to armature reaction of the machine
 reactance either due to armature reaction or leakage flux
 reactance due to leakage flux

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
Consider the following statements about commutating poles which are fitted on most large dc Shunt motors: 1. The commutating poles are placed in the geometric neutral plane and their number is usually Equal to the number of main poles 2. The winding on the commutating poles is connected in series with the shunt-field winding on the main poles 3. The polarity of the commutating pole must be that of the next pole further ahead 4. The commutating poles neutralize the reactance voltage produced in the coil undergoing Commutation. Of these statements,

 1 and 4 are correct
 1, 2 and 4 are correct
 1, 2 and 3 are correct
 2, 3 and 4 are correct

ANSWER DOWNLOAD EXAMIANS APP