Electrical Machines When excitation is increased (over excitation), the synchronous generator operates at leading power factor. lagging power factor. any of the above. unity power factor. leading power factor. lagging power factor. any of the above. unity power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The introduction of interpoles in between the main poles improves the performance of a dc machine, because a counter-emf is induced in the coil undergoing commutation the interpoles produce additional flux to augment the developed torque the inequality of air-gap flux on the top and bottom halves of the armature is removed the flux waveform is improved with reduction in harmonics a counter-emf is induced in the coil undergoing commutation the interpoles produce additional flux to augment the developed torque the inequality of air-gap flux on the top and bottom halves of the armature is removed the flux waveform is improved with reduction in harmonics ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In single phase rotary converter the number of slip rings will be six. three. two. four. six. three. two. four. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the highest possible speed of turbo alternators? 4000 rpm 1000 rpm 3000 rpm 1500 rpm 4000 rpm 1000 rpm 3000 rpm 1500 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-φ alternator has negligible stator resistance. A short circuit test is conducted on this alternator. At a particular speed, a field current of If1 is required to drive the rated armature current. If the speed of the alternator is reduced to half, the field current required to maintain rated armature current Cannot be predicted due to insufficient data. Would be equal to If1. Would be equal to If1/2. Woud be equal to 2If1. Cannot be predicted due to insufficient data. Would be equal to If1. Would be equal to If1/2. Woud be equal to 2If1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of rotation of a 3 - Φ induction motor can be reversed by transposing any two leads from slip rings. disconnecting any one phase. transposing all the three leads from the supply. transposing any two leads from supply. transposing any two leads from slip rings. disconnecting any one phase. transposing all the three leads from the supply. transposing any two leads from supply. ANSWER DOWNLOAD EXAMIANS APP