WorksheetsElectrician 3rd sem Synchronous Motor and MG set
Total questions: 18
Worksheet time: 9mins
What is the name of the converter?
Metal rectifier
Rotary converter
Mercury arc rectifier
Silicon controlled rectifier
What is the name of the converter?
Metal rectifier
Rotary converter
Mercury arc rectifier
Motor-Generator set
Why D.C supply is necessary for synchronous motor operation?
Reduce the losses
Start the motor initially
Run the motor with over load
Run the motor at synchronous speed
Which acts as both inverter and converter?
Metal rectifier
Mercury arc rectifier
Semi conductor diode
Synchronous converter
What is the function of inverter?
Convert A.C to D.C
Convert D.C to A.C
Smoothening A.C sine wave
Convert pulsating DC into pure D.C
Which converting device can be over loaded?
Rectifier unit
Rotary converter
Motor generator set
Mercury arc rectifier
Why exciter is essential to run a synchronous motor?
Carry more load in motor
Improve the power factor
Reduce the losses in motor
Run the motor at synchronous speed
Which application requires only DC?
Electroplating
Stepping up of voltage
Operating induction motor
Operating repulsion motor
Why the LED’s are avoided as converters in rectifier diodes?
Heavily doped device
Very low power device
Designed for light emitting
Very sensitive to temperature
Which is the main application of synchronous motor?
Elevators
Paper rolling mills
AC to DC converter
Power factor correction device
What is the advantage of motor generator set?
Noiseless
High efficiency
Low maintenance required
DC output voltage can be easily controlled
What is the function of the part marked as X of the rotary converter?
Converts AC to DC
Reduces voltage drop
Helps to deliver without noise
Collects the delivered direct current
What is the purpose of damper winding in a synchronous motor at starting?
Produce high voltage to initiate the rotation
Produce high current to start rotate the motor
Produces torque and runs near in synchronous speed
Produce a high magnetic-field to maintain a constant speed
Why the synchronous motor fails to run at synchronous speed?
Insufficient excitation
Defective pony motor
Open in damper winding
Short in damper winding
How the synchronous motor is used as a synchronous condenser?
Varying the motor load
Varying the rotor excitation
Varying stator voltage in motor
Varying stator current in motor
What is the function of damper windings in synchronous motor?
Maintain power factor
Excite the field winding
Maintain constant speed
Start the synchronous motor
Which converter is having high efficiency?
SCR converter
Rotary converter
Motor generator set
Mercury arc rectifier
How synchronous motor works as a power factor corrector?
Varying the line voltage
Varying the field excitation
Increasing the speed of motor
Decreasing the speed of motor
