PYQs Based test 24: Power Electronics

Figure shows 4 electronic switches (i), (ii), (iii) and (iv). Which of the switches can blockVoltages of either polarity(applied between terminals ‘a’ and ‘b’) when the active device is in OFF state?

The output voltage of a single-phase full bridge voltage source inverter is controlled by unipolar PWM with one pulse per half cycle. For the fundamental rms component of output voltage to be 75% of DC voltage, the required pulse width in degrees (round off up to one decimal place) is __________.

A buck-boost DC-DC converter, shown in the figure below, is used to convert $24V$ battery voltage to $36V$ DC voltage to feed a load of $72W$. It is operated at $20kHz$ with an inductor of $2mH$ and output capacitor of $1000\mu F$. All devices are considered to be ideal. The peak voltage across the solid-state switch (S), in volt, is ____________.

A self-commutating switch SW, operated at duty cycle $\delta$ is used to control the load voltage as shown in the figure.



Under steady state operating conditions, the average voltage across the inductor and the capacitor respectively, are

In the following chopper, the duty ratio of switch S is 0.4. If the inductor and capacitor are sufficiently large to ensure continuous inductor current and ripple free capacitor voltage, the charging current (in Ampere) of the $5V$ battery, under steady-state, is____. (the value of resistance is 3 ohms)