Average current in single phase bridge converter SCR

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SUMMARY

The average load current in a single-phase bridge converter using Silicon Controlled Rectifiers (SCRs) is calculated as I(load) / 2, which is a fundamental concept in controlled rectifiers. This division by 2 arises because the load current is shared between two pairs of SCRs during each half-cycle of the AC waveform. The confusion stems from the distinction between average load current and instantaneous current, where the average value reflects the effective current supplied to the load over time. The correct average load current for the given scenario is 3.33A, not 6.66A, as the latter represents the instantaneous current rather than the average.

PREREQUISITES
  • Understanding of controlled rectifiers and their operation
  • Knowledge of single-phase AC circuits
  • Familiarity with SCR (Silicon Controlled Rectifier) characteristics
  • Basic principles of average and RMS current calculations
NEXT STEPS
  • Study the operation of full-wave bridge rectifiers in detail
  • Learn about SCR firing angles and their impact on load current
  • Explore the differences between average current and RMS current in rectifier circuits
  • Investigate the role of each SCR in a bridge converter configuration
USEFUL FOR

Electrical engineering students, power electronics enthusiasts, and professionals working with controlled rectifiers and SCR applications will benefit from this 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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