QUIZ - 1



  1. The maximum speed of prime mover in case of a turbo synchronous generator is
    • 750 rpm
      1500 rpm
      3000 rpm
      6000 rpm


  2. An exciter is nothing but a
    • dc shunt generator
      dc series generator
      dc compound generator
      dc shunt motor


  3. An alternator coupled to which prime mover will usually have the highest rotating speed
    • steam engine
      reciprocating diesel engine
      Francis turbine
      steam turbine


  4. Salient pole type alternator are generally used on
    • low voltage alternator
      hydrogen cooled prime mover
      high speed prime-mover
      low and medium speed prime-mover


  5. The rotor of turbo alternators is usually made up of
    • cast iron
      forged steel
      laminated stainless steel
      manganese steel


  6. When alternator is suppling resistive load
    • the armature reaction flux will be almost zero
      the armature reaction flux will be along the axis of the field
      the armature reaction flux will be at 90 deg. with the field axis
      the armature reaction flux will be at 180 deg. with the field axis


  7. How many electrical degrees in one rotation for a 12 pole alternator -
    • 60 deg.
      360 deg.
      1080 deg.
      2160 deg.


  8. Three phase alternator are usually star connected
    • to save copper
      to reduce conductor size
      to obtain higher terminal voltage
      to reduce windage losses


  9. Short circuit ratio of a turbo alternator is usually
    • 0.5
      0.5 to 0.7
      0.1 to 1.7
      2 to 3


  10. Under which condition hunting of synchronous motor is likely to occur
    • periodic variation of load
      over-excitation
      overload for long time
      small and constant load