ISRO 2023 Quiz 1

In the single-phase voltage controller circuit shown in the figure, for what range of triggering angle (a), the output voltage is not controllable?

Input voltage to the step up (Boost) converter is 20V and output voltage is 50V. If the duty ratio is 0.5 then find the time for which the diodes conduct in each cycle (in µ sec) is ____. (Switching frequency f = 20 kHz)

Therefore the value of equalizing resistance to be used across each thyristor is . The correct statements in respect of IGBT are:

1. It has low input impedance.

2. It combines the good qualities of MOSFET and JFET.

3. It has low ON-state power loss.

4. It is a unipolar device.

A single-phase full bride fully controlled converter is supplying a battery at 100 V for charging application. The converter is connected to 240 V, 50 Hz AC supply. The interconnecting inductor between converter and battery is very large to make the load current flat, continuous and ripple free at 10 A. The inductor has a resistance of 1.5 Ω and assume a voltage drop of 1.5 V for each thyristor. The which of the following statements are true.

1) The operating triggering angle is 57°.

2) Average value of output voltage is 115 V.

3) RMS value of output voltage is 115 V.

4) Converter input power is 1150 W.

Find the unit’s digit in (264)¹⁰² + (264)¹⁰³.