logo

CuriousTab

CuriousTab

Discussion

Home ‣ Electronics and Communication Engineering ‣ Power Electronics Comments
  • Question

  • A single phase step up cycloconverter changes 50 Hz to 100 Hz. Then one half wave of input will give rise to


  • Options
  • A. one half wave of output
  • B. one full wave of output
  • C. two full waves of output
  • D. either (b) or (c)

  • Correct Answer
  • one full wave of output 

    Explanation
    Since output frequency is 2f, one half wave of input must equal one full wave of output.

    Power Electronics problems

    Search Results

    • 1. The two modes of operation of three phase bridge inverters are known as

    • Options
    • A. 60° mode and 120° mode
    • B. 90° mode and 120° mode
    • C. 120° mode and 180° mode
    • D. 120° mode and 240° mode
      • Discuss
    • 2. Assertion (A): A dual converter may be circulating current type or non circulating current type.

      Reason (R): In circulating current dual converter only one converter can be operated at one time.


    • Options
    • A. Both A and R are correct and R is correct explanation of A
    • B. Both A and R correct but R is not correct explanation of A
    • C. A is correct but R is wrong
    • D. A is wrong but R is correct
      • Discuss
    • 3. All inverters use forced commutation.

    • Options
    • A. True
    • B. False
      • Discuss
    • 4. A thyristor needs protection against

    • Options
    • A. high
    • B. high
    • C. both high and high
    • D. either high or high
      • Discuss
    • 5. Space communication links are being increasingly moved into Ka-band (200-30 GHz) because it

    • Options
    • A. offers a much wider available bandwidth
    • B. does not suffer from atmospheric at tenuation
    • C. permits the use of smaller antenna
    • D. does not suffer from rain attenuation
      • Discuss
    • 6. The number of doped regions in a SCR is

    • Options
    • A. 2
    • B. 3
    • C. 4
    • D. 5
      • Discuss
    • 7. A dc circuit breaker must use

    • Options
    • A. natural commutation
    • B. forced commutation
    • C. both natural and forced commutation
    • D. either natural or forced commutation
      • Discuss
    • 8. In a full wave converter (M - 2 connection) feeding an RLE load, the peak thyristor current is 15 A. For fully controlled bridge circuit and same load current, the peak thyristor current will be

    • Options
    • A. 30 A
    • B. 152 A
    • C. 15 A
    • D.
      • Discuss
    • 9. If ton and toff are the turn on and turn off times of a thyristor, then

    • Options
    • A. ton and toff are almost equal
    • B. ton >> toff
    • C. toff >> ton
    • D. ton is about twice toff
      • Discuss
    • 10. In 180° mode of operation of a 3 phase bridge inverter, two thyristors conduct at one time.

    • Options
    • A. True
    • B. False
      • Discuss

    Comments

    There are no comments.
Enter a new Comment




Aptitude

Engineering

Programming

Reasoning

Links

Copyright ©CuriousTab. All rights reserved.