Average and rms value in a diode or thyristor/scr - Please help!

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poosri

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When do you use (2*Vpeak)/3.14 and when do you use just (Vpeak/3.14)

This is just so confusing esp. when going thru' these problems in CI tests....I am very nervous about the power electronics type problems in the exam :wacko:

does anyone have set of formulas on this? (average, rms values etc on power electronics, batteries) - Please share.Thanks a lot!

 
If you have a FULL-WAVE rectified sine wave, the average value is 2*Vpeak/pi, and the RMS value is Vpeak/SQRT(2)

If you have a HALF-WAVE rectified sine wave, the average value is Vpeak/pi, and the RMS value is Vpeak/2

 
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Download the free NCEES Reference manual for the FE exam. It has all those equations for half-wave and full wave rectified sine waves.

 
Can't remember which one it is off the top of my head. In Camara, I think the table shows the circuit, what the waveform looks like, and then equations for Vrms, Vavg, and Vpk.

 
Can't remember which one it is off the top of my head. In Camara, I think the table shows the circuit, what the waveform looks like, and then equations for Vrms, Vavg, and Vpk.


Yeah that table is actually better than the FE Reference. I wasn't aware of it until you pointed it out. Thanks for sharing.

 
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