Q. A 3 phase fully controlled bridge converter is fed by a 3 phase system having phase voltage v = Vm sin ωt. The firing angle is a. The dc output voltage is

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Q. In the circuit of figure, the load current when thyristor is off

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Q. In a step down chopper using time ratio control, the input voltage is V and duty cycle is α. The load is purely resistive having resistance R. The average and rms load currents are

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Q. The symbol in figure is for

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Q. If a step down chopper is fed by a dc voltage V with Ton and Toff are on and off periods then following is

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Q. In the circuit of figure, the waveshape of load current when thyristor conducting is

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Q. In figure, thyristor Th is in off state. When thyristor is turned on, the peak thyristor current can be

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Q. In a single phase full wave converter (M-2 connection) feeding on R-L load the input voltage is v = Vm sin ωt. The expression for rms output voltage is

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Q. A dc chopper is feeding an RLE load. The condition for maximum ripple is

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Q. The symbol in figure is for

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Q. The circuit in figure is for

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Q. The symbol in figure is for

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Q. The turn on characteristics of a power transistor can be assumed to be linear, as shown in the below figure . During turn on time T, voltage reduces linearly from V to 0 and current rises linearly from 0 to I. The energy loss during time T is

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Q. The circuit in figure is for

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Q. If 0.5 T is the time period of oscillations and Toff is the time between turn off of one thyristor and turn on of second thyristor, the frequency of output f of a series inverter is

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Q. In auxiliary commutated chopper fed by voltage V and having L and C commutating elements, the peak value of capacitor current is

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Q. A single phase half wave converter is feeding-a resistor load. The input voltage is v = Vm sin ωt. If firing angle is zero, the output dc voltage Vdc and output rms voltage Vrms respectively

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Q. A single phase converter is fed by a source having an inductance L. If load current is I₀, the decrease in output voltage due to overlap is

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

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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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