MCQs of Symmetrical Fault Analysis (Power System - II - 3150911)

Power System - II (3150911) MCQs

MCQs of Symmetrical Fault Analysis

Showing 41 to 50 out of 55 Questions

41.

The most common type of fault is

(a)	Phase to ground
(b)	Phase to phase
(c)	Two phase to ground
(d)	Three phase to ground

42.

The maximum short circuit current occurs in the case of

(a)	Three phase fault
(b)	Double line to ground fault
(c)	Line to line fault
(d)	Single line to ground fault

43.

For a fault at the terminals of synchronous generator, the fault current is maximum for

(a)	Three phase fault
(b)	Three phase to ground fault
(c)	Single line to ground fault
(d)	Line to line fault

44.

The base impedance of power system is given as

(a)	$\frac{{(Base kV)}^{2}}{Base MVA}$
(b)	$\frac{Base kV}{Base MVA}$
(c)	$\frac{Base MVA}{{(Base kV)}^{2}}$
(d)	$\frac{{(Base MVA)}^{2}}{Base kV}$

45.

For a given base voltage and base volt ampere, per unit impedance value of an element is X. What will be the per unit impedance value of this element when the voltage and volt ampere base are both doubled?

(a)	0.5X
(b)	2X
(c)	4X
(d)	X

46.

Any equipment has per unit impedance of 0.9 pu to a base of 20 MVA, 33 kV. The pu impedance to the base of 50 MVA and 11 kV will be

(a)	4.7
(b)	20.25
(c)	0.9
(d)	10

47.

The impedance per phase of a 3-phase transmission line on the base of 100 MVA, 100 kV is 2 pu. The value of this impedance on a base of 400 MVA and 400 kV would be

(a)	1.5 pu
(b)	1 pu
(c)	0.5 pu
(d)	0.25 pu

48.

The pu impedance of a synchronous machine is 0.242. If the base voltage is increased by 1.1 times, the per unit value will be

(a)	0.266
(b)	0.242
(c)	0.22
(d)	0.2

49.

An isolated synchronous generator with transient reactance of 0.1 pu on a 100 MVA base is connected to the high voltage bus through a step up transformer of reactance 0.1 pu on a 100 MVA base. Fault level at the bus is

(a)	1000 MVA
(b)	500 MVA
(c)	50 MVA
(d)	10 MVA

50.

Four alternators, each rated at 5 MVA, 11 kV, with 20% reactance are working in parallel. The short circuit level at bus is

(a)	6.25 MVA
(b)	20 MVA
(c)	25 MVA
(d)	100 MVA

Showing 41 to 50 out of 55 Questions