Synchronous Generator MCQs Part 8
Contents
- 1 The AC armature winding of an alternator operates at _____________ the field winding
- 2 Turbo-alternators have rotors that have
- 3 The effect of armature reaction in an alternator is minimum at power factor of
- 4 A 3-phase alternator has 3-slots per pole. The distribution factor of winding is
- 5 The rating of an alternator is expressed in
The AC armature winding of an alternator operates at _____________ the field winding
The AC armature winding of an alternator operates at _____________ the field winding
- Much lesser voltage than
- Much higher voltage than
- Same voltage as
- None of the above
Correct answer: 2. Much higher voltage than
Turbo-alternators have rotors that have
Turbo-alternators have rotors that have:
- Large diameter and small axial length
- Small diameter and axial length
- Small diameter and long axial length
- Large diameter and long axial length
Correct answer: 3. Small diameter and long axial length
The effect of armature reaction in an alternator is minimum at power factor of
The effect of armature reaction in an alternator is minimum at power factor of
- 0.866 lagging
- 0.866 leading
- Unity
- 0.5 lagging
Correct answer: 3. Unity
A 3-phase alternator has 3-slots per pole. The distribution factor of winding is
A 3-phase alternator has 3-slots per pole. The distribution factor of winding is:
- 1
- 0.25
- 0.5
- 0.866
Correct answer: 1. 1
Solution: Distribution factor Kd is
Kd = {sin (nβ/2}/{ n sin(β/2)}
Where in the above equation
n = slots per pole per phase
β = Angular displacement between slots = 180° per slots per pole
In the present case n = 3/3 = 1
β = 180°/3 = 60°
Kd = {sin (1*60°/2}/{ 1*sin(60°/2)} = 1
The rating of an alternator is expressed in
The rating of an alternator is expressed in:
- HP
- kW
- kVA
- kVAR
Correct answer: 3. kVA