PYQs Based test 24: Power Electronics

The LC circuit shown in the figure has an inductance L = 1mH and capacitance C = 10 μF. The LC circuit is used to commutate a thyristor, which is initially carrying a current of 5A as shown in the figure below. The values and initial of L and C are same as in previous question. The switch is closed ae t = 0.If the forward drop is negligible, the time taken for the device to turn off is

A single-phase voltage source inverter shown in figure is feeding power to a load. The triggering pulses of the devices are also shown in the figure.





If the load current is sinusoidal and is zero at 0, π, 2π…, the node voltage V${}_{AO}$ has the waveform

A step – up chopper is used is feed a load at 400V dc from a 250V dc source. The inductor current is continuous. If the off time of the switch is 20μs, the switching frequency of the chopper is ______(in kHz)

A single-phase full-bridge voltage source inverter (VSI) is fed from a $300V$ battery. A pulse of $120^o$ duration is used to trigger the appropriate devices in each half-cycle. The rms value of the fundamental component of the output voltage, in volts, is

A buck converter feeding a variable resistive load is shown in the figure. The switching frequency of the switch S is $100kHz$ and the duty ratio is 0.6. The output voltage $V_0$ is $36V$. Assume that all the components are ideal, and that the output voltage is ripple-free. The value of $R$ (in Ohm) that will make the inductor current ($i_L$) just continuous is _________.