PYQs Based test 22: Power Electronics

Consider the buck-boost converter shown. Switch Q is operating at 25 kHz and 0.75 duty-cycle. Assume diode and switch to be ideal. Under the steady-state condition, the average current flowing through the inductor is __________ A.

A single-phase full-bridge inverter fed by a 325 V DC produces a symmetric quasi-square waveform across 'ab' as shown. To achieve a modulation index of 0.8, the angle θ expressed in degrees should be ______. (Round off to 2 decimal places.)

(Modulation index is defined as the ratio of the peak of the fundamental component of V${}_{ab}$ to the applied DC value.)

The figure below shows an uncontrolled diode bridge rectifier supplied from a 220 V, 50 Hz, 1-phase ac source. The load draws a constant current I₀ = 14 A. The conduction angle of the diode D₁ in degrees (rounded off to two decimal places) is ________.

The figure below shows a half-bridge voltage source inverter supplying an RL-load with R = 40 Ω and $L=\left(\frac{0.3}{\pi }\right)H$. The desired fundamental frequency of the load voltage is 50 Hz. The switch control signals of the converter are generated using sinusoidal pulse width modulation with modulation index M = 0.6. At 50 Hz, the RL-load draws an active power of 1.44 kW. The value of DC source voltage V${}_{DC}$ in volts is

A single-phase, full-bridge, fully controlled thyristor rectifier feeds a load comprising a 10 Ω resistance in series with a very large inductance. The rectifier is fed from an ideal 230 V, 50 Hz sinusoidal source through cables which have negligible internal resistance and a total inductance of 2.28 mH. If the thyristors are triggered at an angle α = 45°, the commutation overlap angle in degree (rounded off to 2 decimal places) is _______