Three Phase SemiConverters Objective Questions
Power Electronics Objective Questions & Answers
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A threephase M3 converter is operated from a 3phase, 230 V, 50 Hz supply with load resistance R = 10 Ω. Find the value of firing angle if an average output voltage of 50% of the maximum possible output voltage is required. Hint: α > 30°.
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In the circuit shown below, SCR T1 conducts first. If T1 is fired at an angle of α > 30°, then T1 would conduct from
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In a threephase, threepulse, M3 type controlled converter T1 starts to conduct at 30 + n°. At what angles do T2 and T3 start to conduct? Assume that the conduction sequence is T1T2T3.
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A threephase, threepulse, M3 type controlled converter has firing angle for one of the SCRs set as 15°. This SCR would start conducting at
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A threephase threepulse converter would operate as a line commutated inverter when
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Find the expression for average output voltage at R for the below given configuration. Take firing angle as α = 15°, transformer ratio as 1:1:1 and Vmp as the maximum value of phase voltage at the supply.
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A threephase, threepulse, M3 type controlled converter uses ____________ number of SCRs.
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Find the expression for average output voltage for the given circuit if firing angle is greater than 30°. Take Vmp = secondary side maximum value of phase voltage.
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A threephase three pulse type controlled converter is constructed using 3 SCR devices. The circuit is supplying an R load with α < 30°. As such, each SCR device would conduct for
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A threephase halfwave controlled converter is fed from a 3phase, 400 V source and is connected to a load which takes a constant current of 36 A. Find,the value of average output voltage and average current rating of SCR for a firing angle of 30°.
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