logo

CuriousTab

CuriousTab

Discussion


Home Electronics and Communication Engineering Power Electronics Comments

  • Question
  • The output frequency of a cycloconverter can be changed by changing the firing angle.


  • Options
  • A. True
  • B. False

  • Correct Answer
  • False 


  • Power Electronics problems


    Search Results


    • 1. In a 3 phase full wave regulator feeding a star connected resistance load, firing angle is 75°. Then the number of thyristors conducting at one time is

    • Options
    • A. 1
    • B. 2
    • C. 3
    • D. 4
    • Discuss
    • 2. The specified maximum junction temperature of thyristors is about

    • Options
    • A. 50°C
    • B. 80°C
    • C. 120°C
    • D. 200°C
    • Discuss
    • 3. A 3 phase bridge inverter is fed by 400 V battery. The load is star connected and has a resistance of 10 ? per phase. The peak value of thyristor current is

    • Options
    • A.
    • B.
    • C.
    • D.
    • Discuss
    • 4. In figure, thyristor Th is in off state. When thyristor is turned on, the peak thyristor current can be

    • Options
    • A. 5 A
    • B. 10 A
    • C. 15 A
    • D. 20 A
    • Discuss
    • 5. When an SCR is in forward blocking mode, the applied voltage

    • Options
    • A. appears across only one junction
    • B. is equally shared by two junctions
    • C. is equally shared by three junctions
    • D. may appear across one or more junctions
    • Discuss
    • 6. The minimum gate current which can turn on SCR is called :

    • Options
    • A. trigger current
    • B. holding current
    • C. junction current
    • D. breakover current
    • Discuss
    • 7. In a parallel inverter

    • Options
    • A. each thyristor is turned on twice during each cycle
    • B. each thyristor is turned on once during each cycle
    • C. each thyristor is turned on either once or twice in each load cycle
    • D. each thyristor may be turned on upto four times in each load cycle
    • Discuss
    • 8. When a power diode is conducting, the voltage drop across it is about

    • Options
    • A. I V
    • B. 5 V
    • C. 20 V
    • D. 50 V
    • Discuss
    • 9. In a single phase full wave converter (M-2 connection) feeding on R-L load the input voltage is v = Vm sin ?t. The expression for rms output voltage is

    • Options
    • A.
    • B.
    • C.
    • D.
    • Discuss
    • 10. In thermal ohm's law, temperature and power loss are analogous to

    • Options
    • A. V and I respectively of ohm's law
    • B. I and V respectively of ohm's law
    • C. R and V respectively of ohm's law
    • D. I and R respectively of ohm's law
    • Discuss


    Comments

    There are no comments.

Enter a new Comment