Question

A single phase fully controlled converter is connected to a $240V$ AC supply. If the converter is fired at an advance angle of ${45}^o$ and overlap angle of ${10}^o$, then the mean load voltage is ____ $V$.

• A. -164.9

Answer 1

The correct option is A -164.9
For firing advance angle of ${45}^o$, the full converter is in the inverting mode i.e., $\alpha >{90}^o$
So $\alpha ={180}^o-{45}^o={135}^o$
The mean output voltage,
$V_{ox}=\frac{\text{Maximum mean output voltage at no load}}{2}\times [cos\alpha +cos(\alpha +\mu \left)\right]$
Maximum mean output voltage
$V_{om}=\frac{2V_m}{\pi }$
$V_{0x}=\frac{V_m}{\pi }[cos\alpha +cos(\alpha +\mu \left)\right]$
$=\frac{240\sqrt{2}}{\pi }[cos{135}^o+cos{145}^o]$
$=-164.9V$