Q. The number of leads in a power semiconductor diode are

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Q. If ton and toff are the turn on and turn off times of a thyristor, then

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Q. Assertion (A): The gate current of an SCR is always in the form of pulses.

Reason (R): The gate losses, in pulse triggering, are low.

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Q. The average load current supplied by a thyristor depends on

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Q. In a 3 phase full wave regulator feeding a star connected resistance load the input voltage is 400 V line to line. The firing angle is 160°. The line to line output voltage would be

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Q. A thyristor is reverse biased. A positive gate pulse is applied. The thyristor

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Q. A single phase series converter is used for

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Q. Which of these commutation methods uses an auxiliary SCR?

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Q. In integral cycle control the period of on-off control should be more than mechanical time constant of load.

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Q. A single phase half wave converter is feeding a resistive load. Just before triggering, the voltage across thyristor is

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Q. UJT can be used for

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Q. In a series inverter supplying a load resistance R, the commutating elements L and C should be such that

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Q. In a full wave converter (M - 2 connection) feeding an RLE load, the peak thyristor current is 15 A. For fully controlled bridge circuit and same load current, the peak thyristor current will be

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Q. Induction heating systems require low frequency inverters.

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Q. A single phase half wave controlled rectifier circuit has an R-L load. A freewheeling diode is also in the circuit. When freewheeling diode is conducting the SCR

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Q. An SBS can conduct is one direction only.

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Q. A 750 A circuit uses thyristor of current rating 175 A. If derating is 25%, the number of thyristors in parallel is

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Q. Assertion (A): An inverter does not require forced commutation

Reason (R): A series inverter is a forced commutation inverter.

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Q. In a single phase full wave converter (M - 2 connection), the rms transformer voltage is 300 V across each half of secondary. The PIV for each thyristor is

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Q. A dc separately excited motor has a constant field current. The armature is fed from a single phase supply through a semi-converter. When α = 0, speed is 600 rpm. If α = 90°, the speed is likely to be

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