Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Average current in single phase bridge converter SCR

  1. Dec 31, 2017 #1
    << Mentor Note -- thread moved from the technical forums, so no Homework Template is shown >>

    I'm studying controlled rectifiers and for full wave bridge rectifiers the notes(that I'm studying from says)
    upload_2017-12-31_16-30-44.png
    It says that the average load current is Id / 2
    I don't understand how. Why should the 2 come in formula?
    I tried searching in books but there wasn't any formula for average load current. Just average voltage.
    There is also this question.

    upload_2017-12-31_16-32-3.png
    I'm getting answer as 6.66A
    But they've given answer as 3.33A
    Why will the load current be divided by 2 for average value? I realize this is homework but i'm sort of confused with the concept as to why is average load current divided by 2 in the formula and graph above.

    I guess the thyristor current should be divided by 2 for average value. But why load current?
     

    Attached Files:

    Last edited by a moderator: Dec 31, 2017
  2. jcsd
  3. Dec 31, 2017 #2

    berkeman

    User Avatar

    Staff: Mentor

    It's a little confusing -- could they mean the average load current for each pair of SCRs?
     
  4. Dec 31, 2017 #3
    They haven't mentioned anything. Just this question. And even in the formula they've said I(avg) = I(load)/2
    And then they've stated formula for thyristor RMS current.
     
  5. Jan 2, 2018 #4
    Yep. I admit to being confused also. I also get 6.66 A which means we are either both right or both wrong. Let's know of your progess. Thanks.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted