Q. Two single phase semi-converters are connected in series to form a series converter. The input is v = Vm sin ωt and α1, α2 are the firing angles. If α1 = 0, the dc output voltage is

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Q. A capacitor C farads is charged to a voltage V. It discharges through a thyristor, a diode and an inductance L. The peak current in the circuit is

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Q. A dc chopper feeds an RLE load and has a duty cycle of 1. The load current will be such that

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Q. In a half bridge inverter circuit fed by a battery of voltage V, the rms value of fundamental component of output voltage is

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Q. The symbol in figure is for

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Q. In a parallel inverter the turn off time tq of thyristor and values of commutating elements L and C are related as

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Q. The symbol in figure is for

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Q. If peak value of input voltage is Vm and firing angle is α, the average output voltage for single phase half wave and single phase full wave regulators are

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Q. Assertion (A): The circuit of figure thyristor will conduct for 180° during positive half cycle if it is continuously fired.

Reason (R): A thyristor can conduct only when it is forward biased.

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Q. In the below figure, the load is highly inductive. The firing angle is a for each of the thyristors. The periods of conduction of Th1 and Th2 respectively are

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Q. The condition for underdamped oscillations in a series RLC circuit is

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Q. A single phase fully controlled bridge converter is fed by a voltage Vm sin ωt. The average and rms values of output voltage are

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Q. Which of the following is correct for a BJT?

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Q. A fully controlled bridge converter is feeding an RLE load. The load current is I₀. The input voltage is Vm sin ωt. The KVL equation to find firing angle α is

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Q. The duty cycle of a step down chopper is

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Q. A rectifier is fed by a transformer. The rms voltage and current at secondary of transformer are Vs and Is. Output dc power is Vdc Idc and output ac power is (Vrms ) (Irms), Transformer utilisation factor TUF is

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Q. If Ar and Ac are the amplitudes of reference and control signals, the modulation index M is

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Q. For a single phase half wave converter feeding a resistive load, the firing angle a. The waveshape in below figure is for

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Q. A single phase fully controlled bridge converter is feeding an RLE load. Input voltage is Vm sin ωt and firing angle is α. If average current is I₀, then

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Q. Which of the following is not between F2 layer and D layer?

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