1. We will be in Read Only mode (no new threads, replies, registration) starting at 9:00 EDT for a number of hours as we migrate the forums to upgraded software.

estimation of power dissipation of a resistor when R is very small?

Discussion in 'Homework Help' started by leodavinci90, Nov 15, 2016.

1. leodavinci90 Thread Starter Member

Oct 22, 2014
57
4
Question: if we have a
single-phase full-wave controlled rectifier, ac supply with 50Hz and VS=220Vrms, R=100Ω.
If I have a firing angle =33 degrees and a capacitor is shunted with R, analyse and estimate the resistor power dissipation for small values of C (the ignore smoothing effect), and for medium values of C and sufficiently large values of C (neglect output ripple)

So I know that In any rectifier, the larger the value of any shunt capacitor, we will have a smaller DC voltage across R.
To answer this fully should just use an example calculation such as:
Vr = Vm/(2xfxRxC)
and different ranges of Capacitors from say milli to micro to nano Farad?

Is there another equation for power dissipation?

2. leodavinci90 Thread Starter Member

Oct 22, 2014
57
4
Sorry correction: the title of the thread is wrong
1) small values of C
2) large values of C--> we need to find V(forward voltage of two diodes)