Electrical Engineering: Electrical Machine MCQ
31. Question
A cylindrical rotor generator having internal emf 1 + j0.7 V and terminal voltages (1 + j 00 V). The synchronous reactance is 0.7 pu whereas subtransient reactance is 0.2 pu for 3-φ bolted short circuit at generator the value of subtransient generated internal emf is ______
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32. Question
A cylindrical rotor synchronous generator delivering constant active power at a constant terminal voltage, a current of 100 A at a 0.9 p.f. lagging. A shunt reactor is connected so that the reactive power demand doubles then the new value of armature current is ______ A.
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33. Question
In the given figure, the three windings having polarity as shown above, are connected to 3-φ, balanced supply. The number of turns in the supply winding is 20, the voltage seen in winding X having N = 2 turns will be
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34. Question
If a synchronous motor is running at a leading power factor, its excitation induced voltage (Ef ) is
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35. Question
The figure shows the per-phase representation of a phase-shifting transformer connected between buses 1 and 2 where α is a complex number with non-zero real and imaginary parts.
For the given circuit, Y bus and Z bus are bus admittance matrix and bus impedance matrix, respectively, each of size 2 X 2. Which one of the following statements is true?
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