Average current in single phase bridge converter SCR

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Discussion Overview

The discussion revolves around the calculation of average load current in a single-phase bridge converter using SCRs (Silicon Controlled Rectifiers). Participants are exploring the relationship between the average load current and the current through the thyristors, particularly why the average load current is expressed as Id / 2.

Discussion Character

  • Homework-related, Technical explanation, Conceptual clarification

Main Points Raised

  • One participant questions why the average load current is stated as Id / 2, expressing confusion over the inclusion of the factor of 2 in the formula.
  • Another participant suggests that the average load current might refer to the average for each pair of SCRs in the bridge configuration.
  • A third participant notes that the formula presented states I(avg) = I(load)/2, which adds to the confusion regarding the average current calculations.
  • One participant shares their own calculation of 6.66 A, indicating a potential discrepancy with the provided answer of 3.33 A, and expresses a desire to understand the reasoning behind the average current division.

Areas of Agreement / Disagreement

Participants express confusion regarding the average load current calculation, with no consensus reached on the reasoning behind the division by 2. Multiple interpretations of the formula and its implications are presented.

Contextual Notes

Participants have not provided specific definitions or assumptions that clarify the context of the average load current calculation, leading to uncertainty in the discussion.

jaus tail
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<< Mentor Note -- thread moved from the technical forums, so no Homework Template is shown >> [/color]

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?
 

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jaus tail said:
It says that the average load current is Id / 2
I don't understand how. Why should the 2 come in formula?
It's a little confusing -- could they mean the average load current for each pair of SCRs?
 
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.
 
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.
 
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