Question

The rated field current of an alternator is 2A. This alternator is developing 200V at a field current of 1 A at rated speed. If its field current is made 2A at rated speed, then what would be the generated voltage practically considering armature reaction?
1. < 400 V
2. 380 V
3. 400 V
4. > 400 V

Answer 1

Correct Answer - Option 1 : < 400 V

The rated field current of an alternator is 2A. This alternator is developing 200V at a field current of 1 A at rated speed. If its field current is made 2A at rated speed, then ideally the generating voltage would be 400 V. But practically because of armature reaction the voltage will be less than 400 V.