For the ideal AC-DC rectifier circuit shown in the figure below, the load current magnitude is Idc = 15 A and is ripple free. The thyristors are fired with a delay angle of 45$$^\circ$$. The amplitude of the fundamental component of the source current, in amperes, is _________. (round off to two decimal places).

A 3-phase grid-connected voltage source converter with DC link voltage of 1000 V is switched using sinusoidal Pulse Width Modulation (PWM) technique. If the rid phase current is 10 A and the 3-phase complex power supplied by the converter is given by ($$-$$4000 $$-$$ j3000) VA, then the modulation index used in sinusoidal PWM is _________. (round off to two decimal places).

The steady state current flowing through the inductor of a DC-DC buck boost converter is given in the figure below. If the peak-to-peak ripple in the output voltage of the converter is 1 V, then the value of the output capacitor, in $$\mu$$F, is _________. (round off to nearest integer).

The most commonly used relay, for the protection of an alternator against loss of excitation, is