Electrical circuits-Notes3

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Multiple Choice Questions in Power Electronics - 1

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Multiple Choice Questions on Power System - 3

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Important multiple choice questions on power system 1.        A line trap in carrier current relaying tuned to carrier frequency presents A)      High impedance to carrier frequency but low impedance to power frequency B)       Low impedance to both carrier and power frequency C)       High impedance to both carrier and power frequencies D)      Low impedance to carrier frequency and high impedance to power frequency 2.        The use of fast acting relays and circuit breakers for clearing a sudden short circuit on a transmission link between generator and the receiving end bus improves the transient stability of the machine because A)      Short circuit current becomes zero B)       Post-fault transfer impedance attains a value higher than that during the fault C)       Ordinate of the post-fault power-angle characteristic is higher than that of during fault characteristic D)      Voltage behind the transient reactance increases to a higher value 3.        A
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Multiple choice questions on Power Systems- 4

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