The voltage at the input of an AC-DC rectifier is given by v(ЁЭСб) = 230√2 sin ЁЭЬФЁЭСб where ЁЭЬФ = 2ЁЭЬЛ × 50 rad/s. The input current drawn by the rectifier is given by \(\rm i(t) = 10 \sin \left( \omega t - \frac{\pi}{3} \right) + 4 \sin \left( 3\omega t - \frac{\pi}{6} \right) + 3 \sin \left( 5\omega t - \frac{\pi}{3} \right)\) The input power factor, (rounded off to two decimal places), is, __________ lag.
Only the fundamental current contributes average power with the sinusoidal supply. Total current RMS is \(I_{rms}=\sqrt{(10^2+4^2+3^2)/2}=\sqrt{125/2}\,A\). Thus \(PF=\frac{10}{\sqrt{125}}\cos(\pi/3)=0.4472\approx0.45\), lagging.
Important Questions from Phase Controlled Rectifiers
- Which of the following is control element in Silicon Controlled Resistor (SCR)?
A 240 V single-phase AC supply is fed to a load resistor of 100 Ω through a thyristor. If the thyristor is fired at 90°, what is the power consumed by the load?
The maximum firing angle that can be obtained by a pure resistive trigger circuit used in phase control circuit is:
In a 3-phase converter circuit, during commutation when one SCR in one phase is turned on, turning of an SCR in another phase results is:
If the input frequency of a bridge rectifier is 100 Hz, then the output frequency will be:
