$22-$In the third $($III$)$ interval OF $6$ pulses controlled rectifier$($where $=0),$ the thyristors are working

a$)1$;$2$

b$)2$;$3$

c$)3$;$4$

c$)4$;$5$

$23-$The rms secondary voltage of transformer in the three phase controlled rectifier with $200$ v average load for $30$ is

a$)171$ v b$-222$ v

c$-85$ v

d$-444$ v

$\frac{U_1}{3}=\frac{1}{2}\sqrt[\phantom{2}]{2}{U}_{2}sincodd(x)=\frac{3\sqrt[\phantom{2}]{6}}{2}{U}_{2}cos=1\mathrm{.}17U_{2}cos$

$n_1=\frac{1}{\frac{2}{3}}=\frac{1}{3}=0$

$24-$The anode cathode thyristor for no $1$ in the interval $0t$ of $3$ pulses is determined by

a$)$vea

b$)$ vab

c$)$ vba

d$)$ vac

$25-$The synchronizing relation ships of firing signals in three phase waves are

$1-$GDt $=$; GD $4=+120$

b$-$ GDt $3=+120$;$GJt6=300+$

Got$3=+120$; GDt$6=240+$

d$-$ GD $5=+240$; GJ $6=300+$

A three$-$phase three pulse type controlled converter is constructed using $3$ SCR devices. The ircuit is supplying an R load with As such, each SCR device would conduct for

$60$ each cycle

b$)120$ each cycle

c$)180$ each cycle

d$)360$ each cycle

Find the expression for average output voltage at R for the below given configuration. Take firing angle as $=15,$ transformer ratio as $1$:$1$:$1$ and Vmp as the maximum value of phase voltage at the supply.

a$)(3Vm\frac{p}{2})cos$

b$)(3\sqrt[\phantom{2}]{3}Vm\frac{p}{2})cos$

c$)(3\sqrt[\phantom{2}]{3}Vm\frac{p}{2})sin$

d$)(3Vm\frac{p}{2})sin.$