05/03/2020

DC Chopper Interview Question Answer - 2


1
Which chopper is also called as four quadrant chopper?


Type E chopper


2
What is meant by RLE load?


It is simple motor load in which E indicates back emf of the motor.

3
Which chopper is also called as two quadrant chopper?


Type B chopper and type C chopper

4
Which type of chopper configuration is used in the Jones chopper?


Type D chopper

5
Which circuit provides commutation for the Jones chopper?


The auxiliary SCR, capacitor C, diode and auto transformer provide commutation circuit for the Jones chopper.

6
Which circuit provides commutation for the Morgan chopper?


The capacitor, saturable reactor and diode provide commutation circuit for the Morgan chopper.

7
Comment on the value of the inductance for pre saturation and post saturation of the saturable reactor.


The value of inductance before saturation of the saturable reactor is high whereas its value is low post saturation.

8
How many thyristors the load commutated chopper consists of?


Four

9
Describe the advantages of the load commutated chopper.


Advantages
  • No commutating inductor requires
  • No noise
  • Less costly
  • Low weight
  • It can operate at high frequency therefore minimum requirement of filter
  • Commutates any amount of current


10
Describe the disadvantages of the load commutated chopper.


Disadvantages
  • High switching losses at high frequency
  • Low efficiency in high power applications
  • The peak voltage is twice the supply voltage but it can be reduced by filtering
  • The voltage across freewheeling diode is twice the supply voltage therefore fast recovery diode must be used.


11
Explain the term : Multi phase chopper


Multi phase chopper
  • It is a chopper which consists of two or more than two choppers operating at same frequency and proper phase shift


12
Describe the operating modes of the multi phase choppers.


Operating mode of the choppers
  • Phase shift mode
  • In phase mode


13
Describe the function of source filter in the chopper circuit.


Function of source LC filter in the chopper circuit
The LC filter is connected between supply source and chopper. The LC filter reduces
  • Harmonics
  • Source voltage fluctuation
  • Signal interference
  • Supply distortion


14
State the application of the DC Choppers.


Applications
  • Marine hoists
  • Speed control of induction motor
  • Traction motor control
  • Battery operated vehicles
  • Trolley car




You may also like :

No comments:

Post a comment