AC Generator

Which component of an excitation system is responsible for producing the necessary DC voltage for the generator field winding?

• Brush and slip ring

• Automatic voltage regulator

• Prime mover

• Synchronous condenser

What is the primary function of an excitation system in an AC generator?

• To regulate the prime mover speed.

• To regulate the generator voltage output

• To control the generator's mechanical load.

• To adjust the power factor of the connected load.

In a brushless excitation system, which component is used to convert the AC voltage from the main exciter into DC voltage for the main generator?

• Slip rings

• Pilot exciter

• Rotating diode rectifier

• Armature

Which of the following shows the correct sequence of the brushless excitation system flow?

• • Pilot Exciter→

  • AVR →

  • Main Exciter Stator →

  • Main Exciter Rotor→

  • Rotating Diode →

  • Main Generator Rotor→

  • Main Generator Stator

• • Pilot Exciter→

  • AVR →

  • Main Exciter Rotor →

  • Main Exciter Stator →

  • Rotating Diode →

  • Main Generator Rotor→

  • Main Generator Stator

• • Pilot Exciter→

  • AVR →

  • Main Exciter Stator →

  • Main Exciter Rotor→

  • Rotating Diode →

  • Main Generator Stator→

  • Main Generator Rotor

• • Pilot Exciter→

  • AVR →

  • Main Exciter Stator →

  • Main Exciter Rotor→

  • Rotating Diode →

  • Main Generator Rotor→

  • Main Generator Stator

In A.C generator,by increasing the strength of magnetic field,

• Decrease the Electromotive force (EMF)

• Electromotive force (EMF) becomes zero

• 
  Increases the Electromotive force (EMF)

• Electromotive force (EMF) remains the same

AC generator converts:

• Mechanical energy to electrical energy

• Heat energy to mechanical energy

• 
  

  Electrical energy to mechanical energy

• Chemical energy to electrical energy

According to NEMA MG1-16.48, what is a voltage dip? (NEMA : National Electrical Manufacturers Association)

• A drop in current due to low resistance in a circuit

• The minimum voltage output from a generator under full load
  

• The maximum voltage deviation from rated generator output voltage
  

• A complete loss of voltage in the generator output

Types of generator construction :

• Rotating field generator type

• Rotating armature generator

• Both

What are common causes of voltage dips as described?

• High ambient temperatures and fuel shortages
  

• Inrush currents at motor start-up and heavy block loads
  

• Fluctuating generator frequencies and short circuits
  

• Poor grounding and worn-out generator brushes

Why is an AVR (Automatic Voltage Regulator) needed in a generator system?

• To reduce fuel consumption
  

• To control engine temperature
  

• To stabilize voltage during load changes
  

• To prevent noise from the generator